The Controlled Substances Act (CSA): A Legal Overview for the 119th Congress

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The Controlled Substances Act (CSA):

A Legal Overview for the 119th Congress

Updated January 22, 2025

Congressional Research Service

https://crsreports.congress.gov

R45948

SUMMARY

The Controlled Substances Act (CSA):

A Legal Overview for the 119th Congress

R45948

January 22, 2025

Joanna R. Lampe

Legislative Attorney

The Controlled Substances Act (CSA) establishes a unified legal framework to regulate certain

drugs and other substances that are deemed to pose a risk of abuse and dependence. The CSA

may apply to drugs that are medical or recreational, legally or illicitly distributed, but the statute

does not apply to all drugs. Rather, it applies to drugs and other substances that have been

designated for control by Congress or through administrative proceedings. The CSA also applies

to controlled substance analogues that are intended to mimic the effects of controlled substances and to certain listed

chemicals—chemicals commonly used to manufacture controlled substances.

Controlled substances subject to the CSA are divided into categories known as Schedules I through V based on their medical

utility and their potential for abuse and dependence. Substances considered to pose the greatest risk to the public health and

safety are subject to the most stringent controls and sanctions. A lower schedule number corresponds to greater restrictions,

so substances in Schedule I are subject to the strictest controls, while substances in Schedule V are subject to the least strict.

Many substances regulated under the CSA are also subject to other federal or state regulations, including the Federal Food,

Drug, and Cosmetic Act.

The Drug Enforcement Administration (DEA) is the federal agency primarily responsible for implementing and enforcing the

CSA. DEA may designate a substance for control through notice-and-comment rulemaking if the substance satisfies the

applicable statutory criteria or may undertake such rulemaking to alter or remove existing controls on a controlled substance.

The agency may also place a substance under temporary control on an emergency basis if the substance poses an imminent

hazard to public safety. In addition, DEA may designate a substance for control if required by the United States’ international

treaty obligations. In the alternative, Congress may place a substance under control or modify or remove controls by statute.

The CSA aims to ensure that patients have access to pharmaceutical controlled substances for legitimate medical purposes

while also seeking to protect public health from the dangers of controlled substances diverted into or produced for the illicit

market. To accomplish those two goals, the statute creates two overlapping legal schemes. Registration provisions require

entities working with controlled substances to register with DEA and take various steps to prevent diversion and misuse of

controlled substances. Trafficking provisions establish penalties for the production, distribution, and possession of controlled

substances outside the legitimate scope of the registration system. DEA is primarily responsible for enforcing the CSA’s

registration provisions and works with the Criminal Division of the Department of Justice to enforce the Act’s trafficking

provisions. Violations of the registration provisions generally are not criminal offenses, but certain serious violations may

result in criminal prosecutions yielding fines and even short prison sentences. Violations of the trafficking provisions are

criminal offenses that may result in large fines and lengthy prison sentences.

During the 117th and 118th Congresses, significant legal developments related to controlled substances regulation occurred

via executive branch actions, court decisions, and enacted federal and state legislation. Some Members of Congress also

introduced a number of proposals to amend the CSA in various ways. Recent years saw developments in marijuana law and

policy, including a growing divergence between federal and state marijuana laws, a 2022 presidential grant of clemency for

federal and D.C. marijuana possession offenses, and 2024 DEA rulemaking proceedings proposing to reschedule marijuana

under the CSA. Some Members of the 118th Congress reintroduced legislation such as the MORE Act (H.R. 5601) and the

Cannabis Administration and Opportunity Act (S. 4226), both of which would have removed marijuana from control under

the CSA. Some Members also introduced other bills that would have addressed specific aspects of the divergence between

federal and state marijuana law, including proposals seeking to facilitate clinical research involving marijuana and other

Schedule I controlled substances. In addition, the 118th Congress confronted ongoing issues related to the opioid epidemic,

including the regulation of the powerful opioid fentanyl and its analogues. Some Members of Congress also considered

whether to impose controls on xylazine, an unscheduled veterinary sedative that is sometimes used by humans alone or in

combination with controlled substances.

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The Controlled Substances Act (CSA): A Legal Overview for the 119th Congress

Contents

Background and Scope of the CSA ................................................................................................. 2

Other Regulatory Schemes .............................................................................................................. 4

Federal Food, Drug, and Cosmetic Act ..................................................................................... 4

State Laws Addressing Controlled Substances ......................................................................... 4

Classification of Controlled Substances .......................................................................................... 6

Overview of Schedules ............................................................................................................. 6

Analogues and Listed Chemicals .............................................................................................. 8

Scheduling Procedures .............................................................................................................. 9

Legislative Scheduling ........................................................................................................ 9

Administrative Scheduling................................................................................................ 10

Emergency Scheduling ...................................................................................................... 11

International Treaty Obligations ....................................................................................... 12

Registration Requirements ............................................................................................................ 13

Entities Required to Register................................................................................................... 14

Obligations of Registrants ....................................................................................................... 15

Recordkeeping and Reporting........................................................................................... 15

Inspections ........................................................................................................................ 16

Security ............................................................................................................................. 16

Quotas ............................................................................................................................... 17

Prescriptions...................................................................................................................... 17

Enforcement and Penalties ...................................................................................................... 18

Trafficking Provisions ................................................................................................................... 19

Prohibitions ............................................................................................................................. 19

Enforcement and Penalties ...................................................................................................... 20

Legal Considerations for the 119th Congress ................................................................................ 23

Federal and State Marijuana Regulation ................................................................................. 23

Appropriations Limitations ............................................................................................... 25

Executive Branch Policy and Simple Possession Pardon ................................................. 27

DOJ Proposal to Reschedule Marijuana ........................................................................... 29

Proposed Marijuana Legislation ....................................................................................... 31

Clinical Research and Use of Schedule I Controlled Substances ........................................... 35

Opioid Epidemic ..................................................................................................................... 38

Fentanyl Analogues........................................................................................................... 39

Other Proposals Related to Opioid Regulation ................................................................. 42

Xylazine .................................................................................................................................. 43

Figures

Figure 1. CSA Scheduling Criteria .................................................................................................. 7

Contacts

Author Information........................................................................................................................ 46

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The Controlled Substances Act (CSA): A Legal Overview for the 119th Congress

harmaceutical drugs play a vital role in American public health. Surveys by the Centers

for Disease Control and Prevention (CDC) between 2017 and 2020 estimated that nearly

50% of Americans had used one or more prescription drugs in the last 30 days.1 However,

both pharmaceutical and non-pharmaceutical drugs may also pose serious public health

risks. The CDC reports that 105,007 Americans died of drug overdoses in 2023.2 The

Controlled Substances Act3 (CSA or the Act) seeks to balance those competing considerations.4

The CSA regulates controlled substances—pharmaceutical and non-pharmaceutical drugs and

other substances that are deemed to pose a risk of abuse and dependence.5 By establishing rules

for the proper handling of controlled substances6 and imposing penalties for any illicit production,

distribution, or possession of such substances,7 the Act seeks to protect the public from the

dangers of controlled substances while also ensuring that patients have access to pharmaceutical

controlled substances for legitimate medical purposes.8

This report provides an overview of the CSA and select legal issues that have arisen under the

Act, with a focus on legal issues that may be relevant to the 119th Congress. The report first

summarizes the history of the CSA and explains how the regulation of controlled substances

under the CSA overlaps with other federal and state regulatory regimes.9 It then outlines the five

main categories of substances subject to the Act—known as schedules—and discusses how

substances are added to the schedules.10 The report next outlines the CSA’s registration

requirements, which govern the activities of individuals and entities that register with the

government to receive authorization to handle pharmaceutical controlled substances,11 before

summarizing the CSA’s criminal trafficking provisions, which apply to controlled-substancerelated activities that are not authorized under the Act.12 Finally, the report outlines select legal

considerations for Congress related to the CSA, including the growing divergence between the

1 See National Center for Health Statistics, Therapeutic Drug Use, CDC (Oct. 7, 2024),

https://www.cdc.gov/nchs/fastats/drug-use-therapeutic.htm.

2 See Matthew F. Garnett, M.P.H., and Arialdi M. Miniño, M.P.H., Drug Overdose Deaths in the United States, 20032023, NCHS DATA BRIEF No. 522 (Dec. 2024).

3 Controlled Substances Act, Pub. L. 91-513, tit. II, 84 Stat. 1242 (1970) (codified as amended at 21 U.S.C. §§ 801–

904).

4 See id. §§ 801(1), (2).

5 See id. §§ 802(6), 811. The CSA adopts the definition of “drug” used in the Federal Food, Drug and Cosmetic Act

(FD&C Act) of 1938, ch. 675, 52 Stat 1040. See 21 U.S.C. §§ 802(12), 321(g)(1) (“The term ‘drug’ means (A) articles

recognized in the official United States Pharmacopoeia, official Homoeopathic Pharmacopoeia of the United States, or

official National Formulary, or any supplement to any of them; and (B) articles intended for use in the diagnosis, cure,

mitigation, treatment, or prevention of disease in man or other animals; and (C) articles (other than food) intended to

affect the structure or any function of the body of man or other animals; and (D) articles intended for use as a

component of any article specified in clause (A), (B), or (C).”). The CSA does not apply exclusively to “drugs,”

providing more broadly for the control of any “drug or other substance” included in the CSA’s schedules. 21 U.S.C. §

802(6). Substances subject to the CSA may include plants, such as marijuana or peyote, or chemicals not generally

recognized as drugs. However, for the sake of simplicity, this report at times refers to “drugs” subject to the Act.

6 See id. §§ 821–832.

7 See id. §§ 841–865.

8 See id. §§ 801(1), (2).

9 See infra “Background and Scope of the CSA” and “Other Regulatory Schemes.”

10 See infra “Classification of Controlled Substances.”

11 See infra “Registration Requirements.”

12 See infra “Trafficking Provisions.”

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The Controlled Substances Act (CSA): A Legal Overview for the 119th Congress

status of marijuana under federal and state law, legal limits on clinical research and medical use

of certain controlled substances, and issues related to the opioid epidemic.13

Background and Scope of the CSA

Congress has regulated drugs in some capacity since the 19th century. Federal drug regulation

began with tariffs, import and export controls, and purity and labeling requirements applicable to

narcotic drugs such as opium and coca leaves and their derivatives.14 With the passage of the

Harrison Narcotics Tax Act of 1914, Congress began in earnest to regulate the domestic trade in

narcotic drugs.15 The Harrison Act imposed federal oversight of the legal trade in narcotic drugs

and imposed criminal penalties for illicit trafficking in narcotics.16 Over the course of the 20th

century, the list of drugs subject to federal control expanded beyond narcotic drugs to include

marijuana, depressants, stimulants, and hallucinogens.17

In 1970, Congress revamped federal drug regulation by enacting the Comprehensive Drug Abuse

Prevention and Control Act.18 That act repealed nearly all existing federal substance control laws

and, for the first time, imposed a unified framework of federal controlled substance regulation.19

Title II of the Comprehensive Drug Abuse Prevention and Control Act is known as the Controlled

Substances Act.20

The CSA regulates certain drugs and other substances—whether medical or recreational, legally

or illicitly distributed—that are found to pose a risk of abuse and dependence.21 In enacting the

CSA, Congress recognized two competing interests related to drug regulation. On one hand,

many drugs “have a useful and legitimate medical purpose and are necessary to maintain the

health and general welfare of the American people.”22 On the other hand, “illegal importation,

manufacture, distribution, and possession and improper use of controlled substances have a

substantial and detrimental effect on the health and general welfare of the American people.”23

Accordingly, the Act simultaneously aims to protect the public from the dangers of controlled

substances while ensuring access to controlled substances for legitimate purposes.

To accomplish those two goals, the statute imposes two overlapping legal schemes. Registration

provisions require individuals and entities working with controlled substances to register with the

government, take steps to prevent diversion and misuse of controlled substances,24 and report

13 See infra “Legal Considerations for the 119th Congress.”

14 Thomas M. Quinn & Gerald T. McLaughlin, The Evolution of Federal Drug Control Legislation, 22 CATH. U.L.

REV. 586, 589–93 (1973).

15 Pub. L. No. 63-223, 38 Stat. 785 (1915).

16 Id. See Quinn & McLaughlin, supra note 14 at 593.

17 Id. at 600–03.

18 Pub. L. No. 91-513, 84 Stat. 1236 (1970). Congress has the authority to regulate controlled substances under the

Commerce Clause, U.S. CONST. art. I, § 8, cl. 3. See Gonzales v. Raich, 545 U.S. 1, 15 (2004).

19 Id. See Quinn & McLaughlin, supra note 14, at 605.

20 Title III of the Comprehensive Drug Abuse Prevention and Control Act is the closely related Controlled Substances

Import and Export Act, Pub. L. 91-513, tit. III, 84 Stat. 1285 (1970) (codified as amended at 21 U.S.C. §§ 951–971).

21 See 21 U.S.C. §§ 811, 812.

22 Id. § 801(1).

23 Id. § 801(2).

24 Diversion refers to the movement of controlled substances produced for legal uses from legitimate sources to

unauthorized channels or users. See Program Description, DRUG ENFORCEMENT ADMINISTRATION (DEA),

https://www.deadiversion.usdoj.gov/about-us.html (last visited Jan. 17, 2025).

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The Controlled Substances Act (CSA): A Legal Overview for the 119th Congress

certain information to regulators.25 Trafficking provisions establish penalties for the production,

distribution, and possession of controlled substances outside the legitimate scope of the

registration system.26

The CSA does not apply to all drugs. As discussed below, substances generally must be identified

for control (either individually or as a class) to fall within the scope of the Act.27 For medical

drugs, the CSA primarily applies to prescription drugs, not drugs available over the counter.28

Moreover, the statute does not apply to all prescription drugs but rather to a subset of those drugs

deemed to warrant additional controls.29 As for non-pharmaceutical drugs, well-known

recreational drugs such as cocaine,30 heroin, and lysergic acid diethylamide (LSD) are all

controlled substances, as are numerous lesser-known substances, some of which are identified

only by their chemical formulas.31 Some controlled substances, such as marijuana and fentanyl,

are used for both medical and recreational purposes.32 Some recreational drugs are not classified

as federally controlled substances.33 Alcohol and tobacco, which might otherwise qualify as drugs

potentially warranting control under the CSA, are explicitly excluded from the scope of the Act,34

as is hemp that meets certain statutory requirements.35 It is possible for legitimate researchers and

illicit drug manufacturers to formulate new drugs not listed in any of the Act’s schedules. Even if

those drugs are similar to existing controlled substances, they may fall outside the scope of the

CSA unless they are classified as controlled substances.36 In some cases, however, substances not

specifically listed in the CSA’s schedules may nonetheless be subject to CSA regulation as

controlled substance analogues.37

25 21 U.S.C. §§ 821–832.

26 Id. §§ 841–865.

27 Id. § 811.

Id. § 829; see also infra “Prescriptions.” The U.S. Food and Drug Administration also regulates pharmaceutical

drugs, including pharmaceutical controlled substances, under the FD&C Act. See infra “Federal Food, Drug, and

Cosmetic Act.”

29 DEA has estimated that 10% to 11% of all drug prescriptions written in the United States are for controlled

substances. See Dispensing of Controlled Substances to Residents at Long Term Care Facilities, 75 Fed. Reg. 37463,

37464 (June 29, 2010).

30 Although cocaine is commonly considered a non-pharmaceutical drug, it has been placed in Schedule II, reflecting a

finding that it has an accepted medical use. See 21 C.F.R. § 1308.12(b)(4) (2024); see also infra “Overview of

Schedules.”

31 The full schedules are promulgated at 21 C.F.R. §§ 1308.11–.15.

32 See infra “Federal and State Marijuana Regulation,” and “Opioid Epidemic.”

33 For example, Salvia divinorum (an herb with hallucinogenic effects) and kratom (a tropical tree whose leaves may

have either stimulant or sedative effects depending on dosage) are not subject to the CSA at this writing, although DEA

has identified them as “drugs of concern.” DEA, DRUGS OF ABUSE: A DEA RESOURCE GUIDE, 106–07 (2024).

34 See 21 U.S.C. § 802(6).

35 Id. § 802(16)(B)(i). Hemp and marijuana are both varieties of the cannabis plant. Hemp is defined as “the plant

Cannabis sativa L. and any part of that plant ... with a delta-9 tetrahydrocannabinol concentration of not more than 0.3

percent on a dry weight basis.” 7 U.S.C. § 1639(o). The cannabis plant and most products produced from that plant

remain controlled substances subject to the CSA, unless they meet the statutory definition of hemp. See 21 C.F.R.

§ 1308.11(d)(23) (2024).

36 See The Countdown: Fentanyl Analogues & the Expiring Emergency Scheduling Order: Hearing Before the Sen.

Comm. on the Judiciary, 116th Cong. 1, 4 (2019) (statement of the Amanda Liskamm, Director of Opioid Enforcement

and Preventions Efforts, Office of the Deputy Attorney General, and Greg Cherundolo, Acting Chief of Operations,

Drug Enforcement Administration, U.S. Dep’t of Justice); see also CRS Report R42066, Synthetic Drugs: Overview

and Issues for Congress, by Lisa N. Sacco and Kristin Finklea (2016).

37 See infra “Analogues and Listed Chemicals.”

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The Controlled Substances Act (CSA): A Legal Overview for the 119th Congress

Other Regulatory Schemes

Federal Food, Drug, and Cosmetic Act

Many drugs classified as controlled substances subject to the CSA are also subject to other legal

regimes. For example, all pharmaceutical drugs, including those subject to the Act, are subject to

the Federal Food, Drug, and Cosmetic Act (FD&C Act).38 The U.S. Food and Drug

Administration (FDA) is the agency primarily responsible for enforcing the FD&C Act, which,

among other things, prohibits the “introduction or delivery for introduction into interstate

commerce of any … drug … that is adulterated or misbranded.”39 The FD&C Act defines

misbranding broadly: a drug is considered misbranded if, among other things, its labeling,

advertising, or promotion “is false or misleading in any particular.”40 Unlabeled drugs are

considered to be misbranded,41 as are prescription drugs that FDA has not approved, including

imported drugs.42 The FD&C Act provides that a drug is deemed to be adulterated if, among other

things, it “consists in whole or in part of any filthy, putrid, or decomposed substance,” “it has

been prepared, packed, or held under insanitary conditions,” its container is made of “any

poisonous or deleterious substance,” or its strength, quality, or purity is not as represented.43

The key aims of the FD&C Act are related to but distinct from those of the CSA. The CSA

establishes distribution controls to prevent the misuse of substances deemed to pose a potential

danger to the public welfare.44 The FD&C Act, by contrast, is a consumer protection statute that

seeks to protect consumers from obtaining unsafe or ineffective drugs (and other public health

products) through commercial channels.45 Any person or organization that produces, distributes,

or otherwise works with prescription drugs that are also controlled substances must comply with

the requirements of both the CSA and the FD&C Act.

State Laws Addressing Controlled Substances

In addition to the federal CSA, each state has its own controlled substances laws. With respect to

both pharmaceutical and non-pharmaceutical drugs, many drugs subject to the CSA are also

subject to those state controlled substances laws.46 Such state laws often mirror federal law, and

they are relatively uniform across jurisdictions because almost all states have adopted a version of

38 FD&C Act, ch. 675, 52 Stat 1040 (codified as amended at 21 U.S.C. §§ 301–99i).

39 Id. § 331(a).

40 Id. § 352.

41 See United States v. Wood, 8 F.3d 33, 1993 WL 425948, at *3 (9th Cir. 1993) (table).

42 See, e.g., In re Canadian Import Antitrust Litigation, 470 F.3d 785, 788–90 (8th Cir. 2006); United States v.

Patwardhan, 422 Fed. App’x. 614, 616–17 (9th Cir. 2011). Misbranding also includes misrepresenting that a substance

offered for sale is a brand-name drug. See, e.g., United States v. Xin He, 405 Fed. App’x 220, 221 (9th Cir. 2010). The

FD&C Act also contains a separate provision stating, “No person shall introduce or deliver for introduction into

interstate commerce any new drug,” unless the drug is approved under the FD&C Act. 21 U.S.C. § 355(a).

43 21 U.S.C. § 351.

44 See id. § 801(1) (“The illegal importation, manufacture, distribution, and possession and improper use of controlled

substances have a substantial and detrimental effect on the health and general welfare of the American people.”).

45 See, e.g., United States v. Kordel, 397 U.S. 1, 11 (1970) (invoking the “public interest in protecting consumers

throughout the Nation from misbranded drugs”); see also CRS Report R43609, Enforcement of the Food, Drug, and

Cosmetic Act: Select Legal Issues, by Jennifer A. Staman (2018).

46 ALEX KREIT, CONTROLLED SUBSTANCES: CRIME, REGULATION, AND POLICY 628 (2013).

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The Controlled Substances Act (CSA): A Legal Overview for the 119th Congress

a model statute called the Uniform Controlled Substances Act (UCSA).47 However, states are free

to modify the UCSA, and have done so to varying extents.48 Moreover, the model statute does not

specify sentences for violations, so penalties for state controlled substance offenses vary widely.49

There is not a complete overlap between drugs subject to federal and state controlled substance

laws for several reasons. First, states may elect to impose controls on substances that are not

subject to the CSA.50 For example, some states have controlled the fentanyl analogues

benzylfentanyl and thenylfentanyl, but those substances are not currently scheduled under the

CSA.51 Likewise, some states have taken steps to control the veterinary sedative xylazine.52

Second, states may wish to adopt federal scheduling decisions at the state level but lag behind

federal regulators due to the need for a separate state scheduling process.53 Third, states may

decide not to impose state controls on substances subject to the CSA, or they may choose to

impose modified versions of federal controls at the state level.54

States cannot alter federal law. When state and federal law conflict, the federal law controls.55

Thus, when states “legalize” or “decriminalize” a federally controlled substance (as many have

done recently with respect to marijuana), the sole result is that the substance is no longer

controlled under state law.56 Any federal controls remain in effect and potentially enforceable in

those states.57

47 Richard L. Braun, Uniform Controlled Substances Act of 1990, 13 CAMPBELL L. REV. 365, 365 (1991) (The UCSA

“has been the basic law pertaining to control of narcotic drugs in forty-six (46) states.”).

48 For example, Arkansas has adopted the UCSA but added a sixth schedule for “substances that are determined to be

inappropriately classified by placing them in Schedules I through V.” ARK. CODE ANN. § 5-64-213 (2023). In addition,

the UCSA classifies marijuana as a Schedule I controlled substance subject to stringent controls; however, many states

have passed laws decriminalizing some or all marijuana use. See infra “Federal and State Marijuana Regulation”; see

also Kimberly A. Houser, What Inconsistent Federal Policy Means for Marijuana Business Owners: Washington’s I502 and the Federal Controlled Substances Act, 50 GONZ. L. REV. 305, 308–09 (2015).

49 Braun, supra note 47, at 371; see also Kreit, supra note 46, at 628.

50 Kreit, supra note 46, at 628.

51 See, e.g., United States v. Guerrero, 910 F.3d 72, 75 (2d Cir. 2018) (discussing difference in scheduling between

federal law and Arizona law); McCoy v. United States, 707 F.3d 184 (2d Cir. 2013) (same with respect to Connecticut

law). Benzylfentanyl and thenylfentanyl were temporarily placed under federal control in 1985, but the temporary

scheduling expired in 1986, and DEA has determined that the substances are “essentially inactive, with no evidence of

abuse potential.” Correction of Code of Federal Regulations: Removal of Temporary Listing of Benzylfentanyl and

Thenylfentanyl as Controlled Substances, 75 Fed. Reg. 37300, 37300 (June 29, 2010) (codified at 21 C.F.R. § 1308

(2024)).

52 See, e.g., FLA. STAT. § 893.03 (2024); W.V. CODE § 60A-2-210 (2023). The 118th Congress also considered

proposals to schedule xylazine, but at the time of publication the substance is not scheduled at the federal level. See

infra “Xylazine.”

53 Kreit, supra note 46, at 629.

54 Id. at 628 (citing Ruiz-Vidal v. Gonzales, 473 F.3d 1072, 1078 (9th Cir. 2007)).

55 U.S. CONST. art. VI, cl. 2 (“the laws of the United States ... shall be the supreme law of the land; and the judges in

every state shall be bound thereby, anything in the Constitution or laws of any State to the contrary notwithstanding”).

56 See Gonzales v. Raich, 545 U.S. 1, 29 (2005).

57 DEA and DOJ sometimes do not enforce federal controlled substances law with respect to state-legal activities that

violate the CSA. Reasons for this include the exercise of prosecutorial discretion and the existence of appropriations

riders limiting enforcement of the CSA in some circumstances. For further discussion of the relationship between state

legalization of controlled substances and the CSA, see the “Federal and State Marijuana Regulation” section.

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The Controlled Substances Act (CSA): A Legal Overview for the 119th Congress

Classification of Controlled Substances

The heart of the CSA is its system for classifying controlled substances, as nearly all the

obligations and penalties that the Act establishes flow from the classification system.58 Drugs

become subject to the CSA by being placed in one of five lists, referred to as schedules.59 Either

the administrator of the Drug Enforcement Administration (DEA)60—an agency within the

Department of Justice (DOJ)—or Congress can place a substance in a schedule, move a

controlled substance to a different schedule, or remove a controlled substance from a schedule.61

As discussed below, scheduling decisions by Congress and DEA follow different procedures.62

Overview of Schedules

The CSA establishes five categories of controlled substances, referred to as Schedules I through

V.63 The schedule on which a controlled substance is placed determines the level of restriction

imposed on its production, distribution, and possession, as well as the penalties applicable to any

improper handling of the substance.64 As Figure 1 describes, when DEA places substances under

control by regulation, the agency assigns each controlled substance to a schedule based on its

medical utility and its potential for abuse and dependence.

58 For further discussion of the obligations and penalties that the CSA imposes, see infra “Registration Requirements,”

and “Trafficking Provisions.”

59 21 U.S.C. § 812.

60 The CSA grants the Attorney General the authority to administer its provisions. See, e.g., 21 U.S.C. § 811. The

Attorney General has delegated that authority to the DEA Administrator. See 28 C.F.R. § 0.100(b) (2024).

61 See infra “Scheduling Procedures.”

62 See id.

63 21 U.S.C. § 812.

64 See, e.g., 21 U.S.C. §§ 823 (registration requirements), 829 (prescription requirements),841–842 (prohibitions and

penalties).

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The Controlled Substances Act (CSA): A Legal Overview for the 119th Congress

Figure 1. CSA Scheduling Criteria

Notes:

1 21 U.S.C. § 812(b)(1).

2 The CSA generally uses the word “marihuana” to refer to the cannabis plant and its derivatives. This report

uses the more widely accepted spelling, “marijuana,” unless quoting other sources.

3 For the full list of substances in Schedule I, see 21 C.F.R. § 1308.11 (2024).

4 21 U.S.C. § 812(b)(2).

5 The CSA distinguishes between fentanyl and non-pharmaceutical fentanyl analogues. Fentanyl and several

related medications are in Schedule II. Numerous nonprescription fentanyl-related compounds are in Schedule I.

6 For the full list of substances in Schedule II, see 21 C.F.R. § 1308.12.

7 21 U.S.C. § 812(b)(3).

8 For the full list of substances in Schedule III, see 21 C.F.R. § 1308.13.

9 21 U.S.C. § 812(b)(4).

10 For the full list of substances in Schedule IV, see 21 C.F.R. § 1308.14.

11 21 U.S.C. § 812(b)(5).

12 For the full list of substances in Schedule V, see 21 C.F.R. § 1308.15.

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The Controlled Substances Act (CSA): A Legal Overview for the 119th Congress

A lower schedule number corresponds to greater restrictions, so controlled substances in Schedule

I are subject to the most stringent controls, while substances in Schedule V are subject to the least

stringent.65 Notably, because substances in Schedule I have no accepted medical use in the United

States, it is only legal to produce, dispense, and possess those substances in the context of

federally approved scientific studies.66

Analogues and Listed Chemicals

In addition to the controlled substances listed in Schedules I through V, the CSA also regulates

(1) controlled substance analogues and (2) listed chemicals.

Under the CSA, a controlled substance analogue is a substance that FDA has not approved and

that is not specifically scheduled under the Act, but that has (1) a chemical structure substantially

similar to that of a controlled substance in Schedule I or II or (2) an actual or intended effect that

is “substantially similar to or greater than the stimulant, depressant, or hallucinogenic effect on

the central nervous system of a controlled substance in schedule I or II.”67 A substance that meets

those criteria and is intended for human consumption is treated as a controlled substance in

Schedule I.68 It may seem counterintuitive that an analogue to a Schedule II controlled substance

is treated as if it were a Schedule I controlled substance and thus is subject to more stringent

controls than the substance it mimics. However, substances in Schedules I and II may have a

similarly high potential for abuse. The key difference between those schedules is that Schedule II

controlled substances have an accepted medical use, which controlled substance analogues do not

have because they have not been approved by FDA.

Listed chemicals subject to the CSA are chemicals that are generally not intended for human

consumption but can be used to produce controlled substances either as precursor chemicals or as

part of the manufacturing process.69 They may be placed on one of two lists:

•

List I Chemicals—designated chemicals that, in addition to legitimate uses, are

used in manufacturing a controlled substance in violation of the CSA and are

important to the manufacture of a controlled substance.70

List II Chemicals—designated chemicals that, in addition to legitimate uses, are

used in manufacturing a controlled substance in violation of the CSA.71

List I chemicals include substances such as ephedrine, white phosphorous, and iodine, which are

used to produce methamphetamine, as well as chemicals used to manufacture LSD, MDMA (also

65 See John Doe, Inc. v. DEA, 484 F.3d 561, 563 (D.C. Cir. 2007).

66 See 21 U.S.C. § 823(g); see also Gonzales v. Raich, 545 U.S. 1, 14 (2004).

67 21 U.S.C. § 802(32).

68 Id. § 813(a).

69 See United States v. Hofstatter, 8 F.3d 316, 321–22 (6th Cir. 1993) (in upholding convictions for possession of listed

chemicals with intent to manufacture controlled substance analogues, considering evidence that “the defendants were

attempting to manufacture substances designed for human consumption and designed to produce amphetamine-like

effects when ingested”). It is, however, possible for a substance to be both a listed chemical and a controlled substance

analogue. See 21 U.S.C. § 802(32)(B) (“The designation of gamma butyrolactone or any other chemical as a listed

chemical pursuant to paragraph (34) or (35) does not preclude a finding pursuant to subparagraph (A) of this paragraph

that the chemical is a controlled substance analogue.”); see also United States v. Fisher, 289 F.3d 1329, 1335–36 (11th

Cir. 2002) (finding that a listed chemical could be treated as a controlled substance analogue if intended for human

consumption).

70 21 C.F.R. § 1300.02(b).

71 Id. § 1300.02(b).

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known as “ecstasy” or “molly”), and other drugs.72 List II chemicals include, among others,

solvents such as acetone, hydrochloric acid, and sulfuric acid.73

Listed chemicals are generally less stringently regulated than controlled substances, though they

are subject to some controls similar to those that apply to controlled substances.74 In addition,

entities that sell listed chemicals must record the transactions, report them to regulators, and

comply with statutory limits on sales to a single purchaser.75

There are a number of differences between how controlled substance analogues and listed

chemicals are regulated. In addition, listed chemicals include only specific substances identified

for control under the CSA by statute or rulemaking.76 By contrast, controlled substance analogues

need not be individually scheduled; they need only satisfy the statutory criteria.77

Scheduling Procedures

Substances may be placed under control (often called scheduling), reclassified to a different

schedule (rescheduling), or removed from control (descheduling) through agency action or by

legislation.78 As described below, the procedures for modifying a substance’s scheduling differ

depending on whether Congress or DEA makes the change.

Legislative Scheduling

Perhaps the most straightforward way to change a substance’s legal status under the CSA is for

Congress to pass legislation. The procedural requirements for administrative scheduling discussed

in the next section do not apply to legislative scheduling. This means that scheduling legislation

does not need to incorporate scientific and medical findings and is not subject to the

Administrative Procedure Act (APA).79

Congress placed a number of substances in each schedule when it enacted the CSA in 1970.80

Since the CSA’s enactment, Congress has at times passed legislation to schedule new controlled

substances or modify existing controls.81 Congress has sometimes used its legislative scheduling

power to respond quickly to regulate drugs that pose an urgent concern. For example, the

Synthetic Drug Abuse Prevention Act of 2012 permanently added two synthetic cathinones

(central nervous system stimulants) and certain cannabimimetic substances (commonly referred

to as synthetic marijuana) to Schedule I.82 In 2020, Congress enacted the Temporary

72 Id. § 1310.02(a).

73 Id. § 1310.02(b).

74 See, e.g., 21 U.S.C. §§ 823(h) (requiring DEA registration to distribute List I chemicals), 841(c) (imposing criminal

penalties for, among other things, “possess[ing] or distribut[ing] a listed chemical knowing, or having reasonable cause

to believe, that the listed chemical will be used to manufacture a controlled substance except as authorized by” the

CSA), 842(a) (imposing civil and criminal penalties for certain unauthorized retail sales of listed chemicals).

Id. § 830.

76 21 U.S.C. §§ 802(34), (35).

77 See, e.g., United States v. Hofstatter, 8 F.3d 316, 321–22 (6th Cir. 1993) (upholding against Fifth Amendment

vagueness challenge the statutory criteria for controlled substance analogues).

78 See 21 U.S.C. § 811; United States v. Ways, 832 F.3d 887, 893 (8th Cir. 2016) (summarizing the addition of certain

substances to Schedule I by legislation).

79 Ch. 324, 60 Stat. 237 (1946) (as amended).

80 Comprehensive Drug Abuse Prevention and Control Act, Pub. L. No. 91-513, 84 Stat. 1236 (1970).

81 See generally CRS In Focus IF12709, Legislative Scheduling of Controlled Substances, by Joanna R. Lampe (2024).

82 See Pub. L. No. 112-144, 126 Stat. 1130 (2012).

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Reauthorization and Study of the Emergency Scheduling of Fentanyl Analogues Act, which

placed a broad class of fentanyl analogues in Schedule I on a temporary basis.83

Administrative Scheduling

DEA makes scheduling decisions through a complex administrative process requiring

participation by other agencies and the public.84 DEA may undertake administrative scheduling

on its own initiative, at the request of the U.S. Department of Health and Human Services (HHS),

or “on the petition of any interested party.”85 With regard to the last route for initiating

administrative scheduling, the DEA administrator may deny a petition to begin scheduling

proceedings based on a finding that “the grounds upon which the petitioner relies are not

sufficient to justify the initiation of proceedings.”86 Denial of a petition to initiate scheduling

proceedings is subject to judicial review, but a court may overturn a denial only if it determines

the denial is arbitrary and capricious.87

Before initiating rulemaking proceedings, DEA must request a scientific and medical evaluation

of the substance at issue from the Secretary of HHS.88 The HHS Secretary has delegated the

authority to prepare the scientific and medical evaluation to FDA.89 In preparing the evaluation,

FDA considers a number of factors, including the substance’s potential for abuse and dependence,

scientific evidence of its pharmacological effect, the state of current scientific knowledge

regarding the substance, any risk the substance poses to the public health, and whether the

substance is an immediate precursor of an existing controlled substance.90 Based on those factors,

FDA makes a recommendation as to whether the substance should be controlled and, if so, in

which schedule it should be placed.91 FDA’s scientific and medical findings are binding on

DEA.92 Furthermore, if FDA recommends against controlling a substance, DEA may not schedule

it.93 DEA has stated that it has “the final authority to schedule, reschedule, or deschedule a drug

under the [CSA], after considering the relevant statutory and regulatory criteria and HHS’s

scientific and medical evaluation.”94

83 Pub. L. 116-114, 134 Stat. 103 (2020). For further discussion of the Temporary Reauthorization and Study of the

Emergency Scheduling of Fentanyl Analogues Act and related legislation, see infra “Fentanyl Analogues.”

84 The CSA grants the Attorney General the authority to administer its provisions. See, e.g., 21 U.S.C. § 811. The

Attorney General has delegated that authority to the DEA Administrator, see 28 C.F.R. § 0.100(b), but also retains the

authority to undertake scheduling proceedings, see Schedules of Controlled Substances: Rescheduling of Marijuana, 89

Fed. Reg. 44597, 44601 (proposed May 21, 2024) (to be codified at 21 C.F.R. § 1308).

85 21 U.S.C. § 811(a).

86 21 C.F.R. § 1308.43.

87 See Ams. for Safe Access v. DEA, 706 F.3d 438, 440 (D.C. Cir. 2013).

88 21 U.S.C. § 811(b). DEA may also request a scientific and medical evaluation and subsequently deny a rescheduling

petition. See, e.g., Denial of Petition to Initiate Proceedings to Reschedule Marijuana, 81 Fed. Reg. 53688, 53688

(proposed Aug. 12, 2016).

89 See, e.g., Schedules of Controlled Substances: Placement of Solriamfetol in Schedule IV, 84 Fed. Reg. 27943, 27944

(June 17, 2019).

90 See 21 U.S.C. §§ 811(c)(1)–(8) (full list of factors FDA and DEA must consider in making scheduling decisions).

91 Id. § 811(b).

92 Id.

93 Id.

94 See Letter from Michael D. Miller, Acting Chief, Office of Congressional Affairs, DEA to Earl Blumenauer, U.S.

Representative (Dec. 19, 2023), https://www.documentcloud.org/documents/24253753-dea-letter-to-blumenauer/.

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Upon receipt of FDA’s report, the DEA administrator evaluates all of the relevant data and

determines whether the substance should be scheduled, rescheduled, or removed from control.95

Before placing a substance on a schedule, the DEA administrator must make specific findings that

the substance meets the applicable criteria related to accepted medical use and potential for abuse

and dependence.96 DEA scheduling decisions are subject to the requirements for formal

rulemaking under the APA,97 meaning that interested parties may submit comments and DEA

must provide an opportunity for a hearing on the decision before it becomes final.98

The DEA administrator’s decision whether to schedule, reschedule, or deschedule a substance

through the ordinary administrative process is subject to judicial review.99 Historically, such

review has generally been deferential: Courts have accepted DEA’s interpretation of the CSA as

long as the interpretation of ambiguous statutory text is reasonable,100 and the CSA provides that

the DEA administrator’s findings of fact are “conclusive” on judicial review if the findings are

supported by substantial evidence.101 Overall, courts set aside DEA action “only if it is ‘arbitrary,

capricious, an abuse of discretion, or otherwise not in accordance with law.’”102 It is possible that

the Supreme Court’s 2024 decision in Loper Bright Enterprises v. Raimondo,103 which eliminated

judicial deference to reasonable agency interpretations of ambiguous statutes, will mean that

future DEA scheduling decisions that rely on statutory interpretations will receive less deference

from reviewing courts. Loper Bright will not alter the effect of statutory provisions that

specifically govern judicial review of rulemaking under the CSA, however.104

Emergency Scheduling

Ordinary DEA scheduling decisions made through notice-and-comment rulemaking can take

years to consider and finalize.105 Recognizing that in some cases faster scheduling may be

appropriate, Congress amended the CSA through the Comprehensive Crime Control Act of

1984106 to allow the DEA administrator to place a substance in Schedule I temporarily when

“necessary to avoid an imminent hazard to the public safety.”107 Before issuing a temporary

95 Id. Like FDA, the DEA Administrator is required to consider all the factors in 21 U.S.C. §§ 811(c)(1)–(8) in making

this determination.

96 Id. § 812(b).

97 5 U.S.C. § ch. 5.

98 21 U.S.C. § 811(a); see also Touby v. United States, 500 U.S. 160, 162–63 (1991).

99 See 21 U.S.C. § 877.

100 See All. for Cannabis Therapeutics v. DEA, 930 F.2d 936, 939 (D.C. Cir. 1991) (citing Chevron U.S.A. Inc. v.

Natural Resources Defense Council, Inc., 467 U.S. 837, 843–45 (1984)).

101 21 U.S.C. § 877.

102 See, e.g., Ams. for Safe Access v. DEA, 706 F.3d 438, 449 (D.C. Cir. 2013) (quoting 5 U.S.C. § 706(2)(A)).

103 603 U.S. 369 (2024).

104 Id. For discussion of the Supreme Court’s decision in Loper Bright, see CRS Report R48320, Loper Bright

Enterprises v. Raimondo and the Future of Agency Interpretations of Law, by Benjamin M. Barczewski (2024).

105 See, e.g., Washington v. Barr, 925 F.3d 109, 120 (2d Cir. 2019) (“Plaintiffs document that the average delay in

deciding petitions to reclassify drugs under the CSA is approximately nine years.”). As an example of rescheduling

proceedings that have moved relatively quickly, in October 2022, President Biden directed the Attorney General to

review the status of marijuana under federal law. DOJ and DEA published a notice of proposed rulemaking in the

Federal Register proposing to reschedule marijuana in May 2024. See Schedules of Controlled Substances:

Rescheduling of Marijuana, 89 Fed. Reg. 44597, 44601 (proposed May 21, 2024). As of the publication date of this

report, the agencies have not issued a final rule rescheduling marijuana and a public hearing on the issue remains

pending.

106 Pub. L. No. 98-473, 98 Stat. 1976 (1984).

107 21 U.S.C. § 811(h)(1).

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scheduling order, the DEA administrator must provide 30 days’ notice to the public and the

Secretary of HHS stating the basis for temporary scheduling.108 In issuing a temporary scheduling

order, the DEA administrator must consider only a subset of the factors relevant to permanent

scheduling: the history and current pattern of abuse of the substance at issue; the scope, duration,

and significance of abuse; and the risk to the public health.109 The DEA administrator must also

consider any comments from the Secretary of HHS.110

Pursuant to amendments in the Synthetic Drug Abuse Prevention Act of 2012,111 a substance may

be temporarily scheduled for up to two years; if permanent scheduling proceedings are pending,

the DEA administrator may extend the temporary scheduling period for up to one additional

year.112 If DEA completes the permanent scheduling process for a substance while a temporary

scheduling order is in effect, the temporary scheduling order is vacated.113 The CSA provides that

emergency scheduling orders are not subject to judicial review.114

DEA has recently used its emergency scheduling power to temporarily control a large class of

analogues to the opioid fentanyl,115 other synthetic opioids,116 and several synthetic

cannabinoids.117

International Treaty Obligations

The CSA outlines procedures for scheduling controlled substances based on the United States’

treaty obligations. The United States is a party to the Single Convention on Narcotic Drugs of

1961, which was designed to establish controls on the international and domestic traffic in

narcotics, coca leaf, cocaine, and marijuana.118 The treaty requires signatories, among other

things, to criminalize any “cultivation, production, manufacture, extraction, preparation,

possession, offering, offering for sale, distribution, purchase, sale… importation and exportation

of drugs” that are subject to the Convention, except to the extent the Convention authorizes such

activities.119

108 Id.

109 Id. § 811(h)(3).

110 Id. § 811(h)(4).

111 Pub. L. No. 112-144, 126 Stat. 993 (2012).

112 21 U.S.C. § 811(h)(2). As originally enacted, the Comprehensive Crime Control Act of 1984, Pub. L. No. 98-473,

tit. II, 98 Stat. 1976, 2072, authorized temporary scheduling for up to one year, with a possible extension for up to six

months if permanent scheduling proceedings were pending.

113 21 U.S.C. § 811(h)(5).

114 Id. § 811(h)(6).

115 See Schedules of Controlled Substances: Temporary Placement of Fentanyl-Related Substances in Schedule I, 83

Fed. Reg. 5188 (Feb. 6, 2018); see also infra “Fentanyl Analogues.”

116 See Schedules of Controlled Substances: Temporary Placement of Butonitazene, Etodesnitazene, Flunitazene,

Metodesnitazene, Metonitazene, N-Pyrrolidino etonitazene, and Protonitazene in Schedule I, 87 Fed. Reg. 21556 (Apr.

12, 2022); Schedules of Controlled Substances: Extension of Temporary Placement of Butonitazene, Flunitazene, and

Metodesnitazene in Schedule I of the Controlled Substances Act, 89 Fed. Reg. 25517 (Apr. 11, 2024).

117 See Schedules of Controlled Substances: Temporary Placement of 5F-EDMBPINACA, 5F-MDMB-PICA, FUBAKB48, 5F-CUMYL-PINACA, and FUB-144 into Schedule I, 84 Fed. Reg. 15505 (Apr. 16, 2019).

118 See United Nations Single Convention on Narcotic Drugs, 1961, Mar. 30, 1961, 18 U.S.T. 1407, preamble (stating

the parties’ desire “to conclude a generally acceptable international convention replacing existing treaties on narcotic

drugs, limiting such drugs to medical and scientific use”).

119 Id. art. 36.

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The United States is also party to the Convention on Psychotropic Substances of 1971, which was

designed to establish similar control over stimulants, depressants, and hallucinogens.120 The

Convention on Psychotropic Substances requires parties to adopt various controls applicable to

controlled substances, including mandating licenses for manufacture and distribution, requiring

prescriptions for dispensing such substances, and adopting measures “for the repression of acts

contrary to laws or regulations” adopted pursuant to treaty obligations.121

If existing controls of a drug are less stringent than those required by the United States’ treaty

obligations, the CSA directs the DEA administrator to “issue an order controlling such drug under

the schedule he deems most appropriate to carry out such obligations.”122 Scheduling pursuant to

international treaty obligations does not require the factual findings that are necessary for other

administrative scheduling actions, and may be implemented without regard to the procedures

outlined for regular administrative scheduling.123

Registration Requirements

Once a substance is brought within the scope of the CSA through one of the scheduling processes

discussed above, almost any person or organization that handles that substance, except for the end

user, becomes subject to a comprehensive system of regulatory requirements.124 The goal of the

regulatory scheme is to create a “closed system” of distribution in which only authorized persons

may handle controlled substances.125 Central to the closed system of distribution is the

requirement that individuals or entities that work with controlled substances register with DEA.

Those covered entities, which include manufacturers, distributors, practitioners, and

pharmacists,126 are referred to as registrants.127 DEA has described the movement of a

pharmaceutical controlled substance from the manufacturer to the patient thus:

[A] controlled substance, after being manufactured by a DEA-registered manufacturer,

may be transferred to a DEA-registered distributor for subsequent distribution to a DEAregistered retail pharmacy. After a DEA-registered practitioner, such as a physician or a

dentist, issues a prescription for a controlled substance to a patient .… that patient can fill

that prescription at a retail pharmacy to obtain that controlled substance. In this system, the

manufacturer, the distributor, the practitioner, and the retail pharmacy are all required to

be DEA registrants, or to be exempted from the requirement of registration, to participate

in the process.128

As discussed further below, registrants must maintain records of transactions involving controlled

substances, establish security measures to prevent theft of such substances, and monitor for

suspicious orders to prevent misuse and diversion.129 Thus, the registration system aims to ensure

120 United Nations Convention on Psychotropic Substances, Feb. 21, 1971, 32 U.S.T. 543.

121 Id. art. 2(1)(7).

122 21 U.S.C. § 811(d)(1).

123 Id.

124 See id. § 822.

125 Electronic Prescriptions for Controlled Substances, 75 Fed. Reg. 16236, 16237 (Mar. 31, 2010).

126 21 U.S.C. § 822(a).

127 21 C.F.R. § 1300.02(b)(24).

128 Disposal of Controlled Substances by Persons Not Registered with the Drug Enforcement Administration, 74 Fed.

Reg. 3480, 3481 (Jan. 21, 2009).

129 See infra “Obligations of Registrants.”

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that any controlled substance is always accounted for and under the control of a DEA-registered

person until it reaches a patient or is destroyed.130

Entities Required to Register

Under the CSA, every person who produces, distributes, or dispenses any controlled substance, or

who proposes to engage in any of those activities, must register with DEA, unless an exemption

applies.131 The CSA exempts from registration individual consumers of controlled substances,

such as patients and their family members, whom the Act refers to as “ultimate users.”132 Ultimate

users and other entities exempt from the CSA’s registration provisions can still violate the Act’s

criminal trafficking provisions if they engage in unauthorized activities.133

Manufacturers and distributors of controlled substances, such as pharmaceutical companies, must

hospitals, pharmacies, and individual medical practitioners and pharmacists, may obtain

registrations lasting between one and three years.135 Registrations specify the extent to which

registrants may manufacture, possess, distribute, or dispense controlled substances, and each

registrant may engage only in the specific activities covered by its registration. In some instances,

applicants must obtain more than one registration to comply with the CSA. For example, separate

registrations are required for each principal place of business where controlled substances are

manufactured, distributed, imported, exported, or dispensed.136 Special registration is required for

certain activities, including operating an opioid treatment program such as a methadone clinic.137

The CSA directs the DEA administrator to issue a registration if it would be consistent with the

public interest, and the Act outlines the criteria the DEA administrator must consider when

evaluating the public interest.138 The criteria vary depending on (1) whether the applicant is a

manufacturer, distributor, researcher, or practitioner and (2) the classification of the controlled

substance(s) subject to the application. However, the requirements generally serve to help DEA

determine whether the applicant has demonstrated the capacity to maintain effective controls

against diversion and comply with applicable laws.139

130 See Definition and Registration of Reverse Distributors, 70 Fed. Reg. 22591, 22591 (May 2, 2005).

131 21 U.S.C. § 822; 21 C.F.R. Part 1301. See also 21 U.S.C. § 957 (provision of the Controlled Substances Import and

Export Act, Pub. L. 91-513, tit. III, 84 Stat. 1285 (1970) (codified as amended at 21 U.S.C. §§ 951–71), imposing

registration requirements for importers and exporters of controlled substances).

132 21 U.S.C. § 822(c)(3). See also id. § 802(25) (defining “ultimate user” as a “person who has lawfully obtained, and

who possesses, a controlled substance for his own use or for the use of a member of his household or for an animal

owned by him or by a member of his household”). DEA has explained that ultimate users need not register because the

controlled substances in their possession “are no longer part of the closed system of distribution and are no longer

subject to DEA’s system of corresponding accountability.” Definition and Registration of Reverse Distributors, 68 Fed.

Reg. 41222, 41226 (July 11, 2003). Some other exemptions are specified by statute, see 21 U.S.C. §§ 822(c)(1), (2); or

by regulation, see 21 C.F.R. §§ 1301.22–.24.

133 Cf. United States v. Mancuso, 718 F.3d 780, 798 (9th Cir. 2013) (rejecting an argument that defendant was “merely

‘an ultimate user’” of cocaine because he shared the drug with others, and sharing drugs constitutes “distribution” for

purposes of the CSA’s trafficking provisions, “even if there is no commercial scheme involved”).

134 21 U.S.C. § 822(a)(2).

135 Id. § 822(a)(1).

136 Id. § 822(e)(1).

137 Id. § 823(g); see also CRS In Focus IF10219, Opioid Treatment Programs and Related Federal Regulations, by

Johnathan H. Duff (2019).

138 21 U.S.C. § 823(a)–(f).

139 Id.

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The registration of an individual or organization expires at the end of the registration period

unless it is renewed.140 Registration also ends if revoked by DEA141 or when the registrant dies,

ceases legal existence, or discontinues business or professional practice.142 A registration cannot

be transferred to someone else without the express, written consent of the DEA administrator.143

Obligations of Registrants

Recordkeeping and Reporting

The CSA and its implementing regulations impose multiple recordkeeping and reporting

requirements on registrants. Registrants must undertake a biennial inventory of all stocks of

controlled substances they have on hand and maintain records of each controlled substance they

manufacture, receive, sell, deliver, or otherwise dispose of.144 In addition, subject to limited

exceptions, a controlled substance in Schedule I or II may only be distributed pursuant to a

written order from the recipient of the substance.145 Copies of each order form must be

transmitted to DEA.146 Records of orders must be preserved for two years and made available for

government review upon request.147 Many transactions involving controlled substances are

tracked in the Automation of Reports and Consolidated Orders System (ARCOS), an automated

drug reporting system maintained by DEA.148

Registrants are also required to “design and operate a system to identify suspicious orders” and to

notify DEA of any suspicious orders they detect.149 DEA regulations that apply to nonpractitioners provide that “[s]uspicious orders include orders of unusual size, orders deviating

substantially from a normal pattern, and orders of unusual frequency.”150 That list is not

exhaustive. Courts have suggested that orders may be suspicious if, for example, a pharmacy

mostly sells controlled substances rather than a more typical mix of controlled and non-controlled

medications, many customers pay for controlled substances with cash, or pharmacies purchase

drugs at a price higher than insurance would reimburse.151 DEA initiated rulemaking on

suspicious order reporting in 2020 but, as of January 2025, has not issued a final rule.152 The

agency issued a guidance document on suspicious order reporting in 2023 stating that DEA140 21 C.F.R. § 1301.13(c), (d).

141 Id. § 1301.36. The fact that a registrant allows its registration to expire or otherwise terminate during the pendency

of an enforcement action does not impact DEA’s jurisdiction or prerogative under the CSA to adjudicate the action to

finality. See Jeffrey D. Olsen, M.D.; Decision and Order, 84 Fed. Reg. 68474, 68476–68479 (Dec. 16, 2019). For

additional discussion of revocation of registration, see infra “Enforcement and Penalties.”

142 21 C.F.R. § 1301.52.

143 Id. § 1301.52(b).

144 21 U.S.C. § 827; 21 C.F.R. Part 1304.

145 21 U.S.C. § 828; 21 C.F.R. Part 1305.

146 21 U.S.C. § 828(c)(2).

147 Id. § 828(c)(1).

148 DEA, Automation of Reports and Consolidated Orders System (ARCOS), DOJ,

https://www.deadiversion.usdoj.gov/arcos/arcos.html (last visited Jan. 13, 2025).

149 Id. § 832.

150 21 C.F.R. § 1304.74(b).

151 See Masters Pharmas. Inc. v. DEA, 861 F.3d 206, 220 (D.C. Cir. 2017). Masters concerned the alleged failure of a

pharmaceutical distributor to report to DEA suspicious orders for controlled substances and to take other precautions to

ensure that those medications would not be diverted into illegal channels. See id. at 211–12. Pharmacies themselves

have a corresponding responsibility to ensure that they are filling legitimate prescriptions. See 21 C.F.R. § 1306.04(a).

152 Suspicious Orders of Controlled Substances, 85 Fed. Reg. 69282 (proposed Nov. 2, 2020).

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registered manufacturers or distributors are not required to set quantitative thresholds for orders

of controlled substances.153

Inspections

The CSA permits the DEA administrator to inspect the establishment of any registrant or

applicant for registration.154 DEA regulations express the agency’s intent “to inspect all

manufacturers of controlled substances listed in Schedules I and II and distributors of controlled

substances listed in Schedule I once each year,” and other manufacturers and distributors of

controlled substances “as circumstances may require.”155 Absent the consent of the registrant or

special circumstances such as an imminent danger to health or safety, a warrant is required for

inspection.156 “Any judge of the United States or of a State court of record, or any United States

magistrate judge” may issue such a warrant “within his territorial jurisdiction.”157 Issuance of a

warrant requires probable cause.158 The CSA defines probable cause as “a valid public interest in

the effective enforcement of this subchapter or regulations thereunder sufficient to justify” the

inspection at issue.159

Security

The CSA’s implementing regulations require all registrants to “provide effective controls and

procedures to guard against theft and diversion of controlled substances.”160 The regulations

establish specific physical security requirements, which vary depending on the type of registrant

and the classification of the controlled substance at issue.161 For example, practitioners162 subject

to CSA registration must store controlled substances “in a securely locked, substantially

constructed cabinet.”163 In addition to those physical security requirements, practitioners may not

“employ, as an agent or employee who has access to controlled substances,” any person who has

been convicted of a felony related to controlled substances, had an application for CSA

registration denied, had a CSA registration revoked, or surrendered a CSA registration for

cause.164 Registered non-practitioners must store controlled substances in Schedules I and II in a

153 DEA, DIVERSION CONTROL DIVISION, GUIDANCE DOCUMENT: DEA-REGISTERED MANUFACTURER AND DISTRIBUTOR

ESTABLISHED CONTROLLED SUBSTANCE QUANTITATIVE THRESHOLDS AND THE REQUIREMENT TO REPORT SUSPICIOUS

ORDERS (Jan. 20, 2023), https://www.deadiversion.usdoj.gov/GDP/(DEA-DC-065)(EODEA258)_Q_A_SOR_and_Thresholds_(Final).pdf.

154 21 U.S.C. § 822(f).

155 21 C.F.R. §1316.13.

156 21 U.S.C. § 880(c).

157 Id. § 880(d)(1).

158 Id.

159 Id. The CSA’s definition of probable cause is conceptually distinct from what is required under the Fourth

Amendment. See United States v. Schiffman, 572 F.2d 1137, 1139–40 (5th Cir. 1978).

160 21 C.F.R. § 1301.71.

161 Id. §§ 1301.72–76.

162 The CSA defines “practitioner” to include any “physician, dentist, veterinarian, scientific investigator, pharmacy,

hospital, or other person licensed, registered, or otherwise permitted, by the United States or the jurisdiction in which

he practices or does research, to distribute, dispense, conduct research with respect to, administer, or use in teaching or

chemical analysis, a controlled substance in the course of professional practice or research.” 21 U.S.C. § 802(21). The

CSA and its implementing regulations do not define the term “non-practitioner,” but it appears to include registrants

not engaged in the practice of medicine, such as manufacturers and distributors.

163 21 C.F.R. § 1301.75(a), (b). A securely locked closet or room may satisfy this requirement if sufficient to prevent

theft or diversion. See, e.g., Ajay S. Ahuja, M.D.; Decision and Order, 84 Fed. Reg. 5479, 5493–94 (Feb. 21, 2019).

164 Id. § 1301.76(a).

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safe, steel cabinet, or vault that meets certain specifications.165 Non-practitioners must further

ensure that controlled substance storage areas are “accessible only to an absolute minimum

number of specifically authorized employees.”166

Quotas

To prevent the production of excess amounts of controlled substances, which may increase the

likelihood of diversion, the CSA directs DEA to set aggregate production quotas for controlled

substances in Schedules I and II and for ephedrine, pseudoephedrine, and

phenylpropanolamine.167 The DEA administrator is also required to set individual quotas for each

registered manufacturer seeking to produce such substances and to limit or reduce individual

quotas as necessary to prevent oversupply.168 With respect to certain opioid medications, the Act

further directs the DEA administrator to estimate the amount of diversion of each opioid and

reduce quotas to account for such diversion.169 DEA sets production quotas annually and can

adjust the quotas for a calendar year based on changes in demand.170

Relatedly, the Controlled Substances Import and Export Act allows the importation of certain

controlled substances and listed chemicals only in amounts the DEA administrator determines to

be “necessary to provide for the medical, scientific, or other legitimate needs of the United

States.”171

Prescriptions

Under the CSA, controlled substances in Schedules II through IV must be provided directly to an

ultimate user by a medical practitioner or dispensed pursuant to a prescription.172 The Act does

not mandate that Schedule V substances be distributed by prescription, but such substances may

be dispensed only “for a medical purpose.”173 As a practical matter, Schedule V substances are

usually dispensed pursuant to a prescription due to separate requirements under the FD&C Act or

state law.174 DEA regulations provide that a prescription for a controlled substance “must be

165 21 C.F.R. § 1301.72(a).

166 Id. § 1301.72(d).

167 21 U.S.C. § 826(a); see also 21 C.F.R. § 1303.11. Ephedrine, pseudoephedrine, and phenylpropanolamine are List I

chemicals that may be used in the manufacture of controlled substances such as methamphetamine or amphetamine.

See DEA, LISTED CHEMICALS REGULATED UNDER THE CONTROLLED SUBSTANCES ACT (Dec. 31, 2024),

https://www.deadiversion.usdoj.gov/schedules/orangebook/j_chemlist_regulated.pdf.

168 21 U.S.C. § 826(b), (c).

169 Id. § 826(i).

170 See 21 C.F.R. § 1303.13. See also, e.g., Established Aggregate Production Quotas for Schedule I and II Controlled

Substances and Assessment of Annual Needs for the List I Chemicals Ephedrine, Pseudoephedrine, and

Phenylpropanolamine for 2020, 84 Fed. Reg. 66014, (Dec. 2, 2019) (setting aggregate production quotas for 2020);

Adjustments to Aggregate Production Quotas for Certain Schedule II Controlled Substances and Assessment of Annual

Needs for the List I Chemicals Ephedrine and Pseudoephedrine for 2020, in Response to the Coronavirus Disease 2019

Public Health Emergency, 85 Fed. Reg. 20302 (Apr. 10, 2020) (adjusting aggregate production quotas for 2020 to meet

increased need due to the COVID-19 pandemic).

171 21 U.S.C. § 952. The Controlled Substances Import and Export Act, Pub. L. 91-513, tit. III, 84 Stat. 1285 (1970),

(codified as amended at 21 U.S.C. §§ 951–71), also imposes controls on the exportation of controlled substances, but

does not establish specific export quotas. See 21 U.S.C. § 953.

172 21 U.S.C. § 829(a), (b). Substances in Schedule I may not be dispensed by prescription because they have no

accepted medical use in treatment in the United States.

173 Id. § 829(c).

174 Cf., e.g., GA. CODE § 16-13-29.2 (2023) (permitting the State Board of Pharmacy to allow the sale of Schedule V

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issued for a legitimate medical purpose by an individual practitioner acting in the usual course of

his professional practice.”175 Both practitioners who prescribe controlled substances and

pharmacists who fill controlled substance prescriptions bear responsibility for ensuring

compliance with the applicable requirements.176

Enforcement and Penalties

DEA is the federal agency primarily responsible for enforcing the CSA’s registration

requirements.177 DEA may take formal or informal administrative action to enforce the

registration requirements, including issuing warning letters, suspending or revoking an entity’s

registration, and imposing fines.178 The DEA administrator’s decisions related to CSA

registrations are published in the Federal Register.179

The DEA administrator may suspend or revoke a registration (or deny an application for

registration) on several bases, including findings that a registrant or applicant has materially

falsified his application, has been convicted of certain felonies, does not have state authority to

handle controlled substances, or has “committed such acts as would render his registration …

inconsistent with the public interest.”180 Unless the DEA administrator finds that there is an

imminent danger to the public health or safety, the DEA administrator must provide the applicant

or registrant with notice, the opportunity for a hearing, and the opportunity to submit a corrective

plan before denying, suspending, or revoking a registration.181 Imminent danger exists when, due

to the failure of the registrant to comply with the registration requirements, “there is a substantial

likelihood of an immediate threat that death, serious bodily harm, or abuse of a controlled

substance will occur in the absence of an immediate suspension of the registration.”182 To

illustrate, those conditions may be satisfied when a practitioner prescribes controlled substances

outside the usual course of professional practice, without a legitimate medical purpose, and

controlled substances without a prescription); FLA. STAT. § 893.08 (2024) (permitting the sale of Schedule V controlled

substances over-the-counter by a registered pharmacist, if a prescription is not required under the FD&C Act).

175 21 C.F.R. § 1306.04(a).

176 Id.

177 See 28 C.F.R. § 0.100(b) (delegating to the Administrator of DEA functions that relate to, arise from, or supplement

investigations of matters concerning drugs under the Comprehensive Drug Abuse Prevention and Control Act of 1970,

Pub. L. No. 91-513, 84 Stat. 1236).

178 See 21 U.S.C. §§ 822(f), 824(a), 842(c), 842(d). A person who must register under the CSA but fails to do so is

subject to prosecution under the Act’s general trafficking provisions. See United States v. Blanton, 730 F.2d 1425,

1429–30 (11th Cir. 1984); see also infra “Trafficking Provisions.”

179 See, e.g., Ajay S. Ahuja, M.D.; Decision and Order, 84 Fed. Reg. 5479, 5493–94 (Feb. 21, 2019).

180 21 U.S.C. §§ 823, 824(a).

181 Id. § 824(c), (d). Enforcement actions based on imminent danger are not subject to these requirements, but DEA

provides an administrative review process for any denial, suspension, or revocation of registration, and a registrant may

seek judicial review of the agency’s final decision under the Administrative Procedure Act, ch. 324, 60 Stat. 237 (1946)

(as amended). See, e.g., Volkman v. DEA, 567 F.3d 215, 219 (6th Cir. 2006).

182 21 U.S.C. § 824(d)(2). Congress added the opportunity to submit a corrective plan and the standard for determining

whether an imminent danger to the public health or safety exists through the Ensuring Patient Access and Effective

Drug Enforcement Act of 2016, Pub. L. No. 114-145, 130 Stat. 354 (2016). Those amendments made it more difficult

for DEA to issue immediate suspensions. Previously, the CSA simply provided that “[t]he Attorney General [through

the DEA Administrator] may, in his discretion, suspend any registration simultaneously with the institution of

proceedings under this section, in cases where he finds that there is an imminent danger to the public health or safety.”

21 U.S.C. § 824(d) (2000). As amended, the CSA limits DEA’s discretion by requiring a specific finding of “imminent

threat [of] death, serious bodily harm, or abuse of a controlled substance.” 21 U.S.C. § 824(d)(2); see also Scott

Higham & Lenny Bernstein, The Drug Industry’s Triumph over the DEA, WASH. POST, Oct. 15, 2017.

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beneath the applicable standard of care in violation of state and federal controlled substances

laws.183

A violation of the CSA’s registration requirements—including failure to maintain records or

detect and report suspicious orders, noncompliance with security requirements, or dispensing

controlled substances without the necessary prescriptions—generally does not constitute a

criminal offense unless the violation is committed knowingly.184 However, in the event of a

knowing violation, DOJ may bring criminal charges against both individual and corporate

registrants. Potential penalties vary depending on the offense. For example, a first criminal

violation of the registration requirements by an individual is punishable by a fine or up to a year

in prison.185 If “a registered manufacturer or distributor of opioids” commits knowing violations

such as failing to report suspicious orders for opioids or maintain effective controls against

diversion of opioids, the registrant may be punished by a fine of up to $500,000 for each

registration violation.186

Trafficking Provisions

In addition to the registration requirements outlined above, the CSA contains provisions that

define offenses involving the production, distribution, and possession of controlled substances

outside the legitimate confines of the registration system—what this report refers to as the Act’s

trafficking provisions.187 Although the word “trafficking” may primarily call to mind the illegal

distribution of recreational drugs, the CSA’s trafficking provisions apply to a wide range of illicit

activities involving either pharmaceutical or non-pharmaceutical controlled substances.188

Prohibitions

Key sections of the CSA’s trafficking provisions make the following activities illegal, unless

otherwise authorized under the Act:

•

Manufacture of a controlled substance,189 which includes the synthesis of a

controlled substance that is a chemical, the cultivation of a controlled substance

that is a plant, or the processing or packaging of a controlled substance;190

183 See Akhtar-Zaidi v. DEA, 841 F.3d 707, 710 (6th Cir. 2016). The court in Akhtar-Zaidi found that a physician

violated federal and state law “by (1) prescribing medication without patients’ addresses, (2) overstating the nature and

extent of examinations conducted and pain levels reported by patients, and (3) failing to comply with state requirements

relating to the treatment of chronic pain,” and thus “created a substantial likelihood that abuse of controlled substances

would occur in the absence of an immediate suspension.” Id. at 710, 713.

184 21 U.S.C. § 842(c)(1).

185 Id. § 842(c)(2)(A).

186 Id. § 842(c)(2)(D).

187 See id. §§ 841–865.

188 See, e.g., id. §§ 841, 844 (criminalizing the manufacture, distribution, and possession of “a controlled substance,”

except as authorized by the CSA).

189 Id. § 841(a)(1).

190 Id. § 802(15) (“‘manufacture’ means the production, preparation, propagation, compounding, or processing of a

drug or other substance, either directly or indirectly or by extraction from substances of natural origin, or independently

by means of chemical synthesis or by a combination of extraction and chemical synthesis, and includes any packaging

or repackaging of such substance or labeling or relabeling of its container”); 802(22) (“‘production’ includes the

manufacture, planting, cultivation, growing, or harvesting of a controlled substance”).

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•

Distribution or dispensing of a controlled substance;191

Possession of a controlled substance with or without intent to distribute.192

Penalties for the foregoing offenses vary based on the type and amount of the controlled

substance in question.193 Other sections of the CSA define more specific offenses, such as

distributing controlled substances at truck stops or rest areas,194 at schools,195 or to people under

age 21;196 endangering human life while manufacturing a controlled substance;197 selling drug

paraphernalia;198 and engaging in a “continuing criminal enterprise”—that is, an ongoing drug

dealing operation that involves at least five other people and provides the defendant with

substantial income or resources.199 An attempt or conspiracy to commit any offense defined under

the Act also constitutes a crime.200

Enforcement and Penalties

DOJ enforces the CSA’s trafficking provisions by bringing criminal charges against alleged

violators.201 Notably, the CSA’s registration system and its trafficking regime are not mutually

exclusive, and participation in the registration system does not insulate registrants from the

statute’s trafficking penalties. In the 1975 case United States v. Moore, the Supreme Court

rejected a claim that the CSA “must be interpreted in light of a congressional intent to set up two

separate and distinct penalty systems,” one for registrants and one for persons not registered

under the CSA.202 The Court in Moore held that physicians registered under the CSA can be

prosecuted under the CSA’s general drug trafficking provisions “when their activities fall outside

the usual course of professional practice.”203

Numerous judicial opinions provide guidance on what sorts of conduct fall outside the usual

course of professional practice. The defendant in Moore was a registered doctor who distributed

large amounts of methadone with inadequate patient exams and no precautions against misuse or

diversion. The Court held that “[t]he evidence presented at trial was sufficient for the jury to find

that respondent’s conduct exceeded the bounds of ‘professional practice’” because, “[i]n practical

effect, he acted as a large-scale ‘pusher’—not as a physician.”204 Appellate courts have relied on

191 21 U.S.C. § 841(a)(1). “Dispensing” refers to delivery of a controlled substance by a registered practitioner,

including prescribing or administering a pharmaceutical controlled substance, while “distribution” refers to other

delivery of a controlled substance. Id. § 802(10), (11).

192 Id. § 841(a)(1) (criminalizing possession with intent to manufacture, distribute, or dispense, a controlled substance,

except as authorized under the CSA); id. § 844(a) (making it unlawful “knowingly or intentionally to possess a

controlled substance,” unless the substance was obtained in a manner authorized by the CSA).

193 See, e.g., id. § 841(b).

194 Id. § 849.

195 Id. § 860.

196 Id. § 859.

197

Id. § 858.

198 Id. § 863.

199 Id. § 848.

200 Id. § 846.

201 Trafficking that involves smuggling may also implicate the Controlled Substances Import and Export Act, Pub. L.

91-513, tit. III, 84 Stat. 1285 (1970) (codified as amended at 21 U.S.C. §§ 951–971), and/or the Maritime Drug Law

Enforcement Act, Pub L. No. 96-350, 94 Stat. 1159 (1980) (codified as amended at 46 U.S.C. §§ 70501–70508).

202 423 U.S. 122, 133 (1975).

203 Id. at 124.

204 Id. at 142–43.

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Moore to uphold convictions of a pharmacist who signed thousands of prescriptions for sale

through an online pharmacy205 and a practitioner who “freely distributed prescriptions for large

amounts of controlled substances that are highly addictive, difficult to obtain, and sought after for

nonmedical purposes.”206 However, several courts cautioned that a conviction under Moore

requires more than a showing of mere professional malpractice. For instance, the U.S. Court of

Appeals for the Ninth Circuit (Ninth Circuit) has held that the prosecution must prove that the

defendant “acted with intent to distribute the drugs and with intent to distribute them outside the

course of professional practice,” suggesting that specific intent must be established with respect

to the defendant’s failure to abide by professional norms.207

In the 2022 case Ruan v. United States, the Supreme Court clarified the mental state required to

convict a medical practitioner for violation of the CSA’s trafficking provisions.208 The Court held

that, “[a]fter a defendant produces evidence that he or she was authorized to dispense controlled

substances”—that is, that he or she was registered to do so under the CSA—“the Government

must prove beyond a reasonable doubt that the defendant knew that he or she was acting in an

unauthorized manner, or intended to do so.”209 This means that the government must show that a

CSA registrant knowingly or intentionally dispensed a controlled substance not for a legitimate

medical purpose or in a manner that was not in the usual course of professional practice.210

For decades, DOJ has brought criminal trafficking charges against practitioners who dispensed

pharmaceutical controlled substances outside the usual course of professional practice, without a

legitimate medical purpose, and beneath the applicable standard of care.211 In April 2019, DOJ for

the first time brought criminal trafficking charges against a pharmaceutical company that

distributed controlled substances—Rochester Drug Cooperative—and two of its executives based

on the company’s sale of the opioids oxycodone and fentanyl to pharmacies that illegally

dispensed the drugs.212 Similarly, in July 2019, a federal grand jury indicted two former

205 See United States v. Nelson, 383 F.3d 1227, 1230 (10th Cir. 2004).

206 United States v. McIver, 470 F.3d 550, 564 (4th Cir. 2006).

207 United States v. Feingold, 454 F.3d 1001, 1008 (9th Cir. 2006) (emphasis in original); see also United States v.

Armstrong, 550 F.3d 382, 401 (5th Cir. 2008) (explaining that “the mens rea of a § 841 offense is encompassed in the

second and third element of the crime—whether the practitioner intentionally dispensed controlled substances without a

legitimate medical purpose or outside the scope of professional practice,” and distinguishing “a § 841 prosecution from

a mere civil malpractice suit where a plaintiff may prevail regardless of a defendant doctor’s good faith intent to act

within the scope of medical practice”); United States v. Schneider, 704 F.3d 1287, 1295 (10th Cir. 2013) (approving

jury instructions “nearly identical” to those upheld in Feingold and holding that “the jury, on the instructions given,

found that [the defendant] knowingly acted not for a legitimate medical purpose or not within the usual course of

professional practice”).

208 597 U.S. 450 (2022).

209 Id. at 454.

210 Id. at 466–67.

211 See, e.g., Moore, 423 U.S. 122; Press Release, DEA, Multiple Cases Lead to Arrests of Five Doctors, One

Pharmacist, One Nurse Practitioner and Three Others (Oct. 11, 2018), https://www.dea.gov/pressreleases/2018/10/11/multiple-cases-lead-arrests-five-doctors-one-pharmacist-one-nurse; Press Release, DEA, DEA

Large-scale Operation Targets 26 Pharmacies in Three States in Attack Against Illicit Opioid Abuse and Trafficking

(Dec. 5, 2017), https://www.dea.gov/press-releases/2017/12/05/dea-large-scale-operation-targets-26-pharmacies-threestates-attack.

212 See Press Release, DOJ, Manhattan U.S. Attorney and DEA Announce Charges Against Rochester Drug CoOperative and Two Executives for Unlawfully Distributing Controlled Substances (Apr. 23, 2019),

https://www.justice.gov/usao-sdny/pr/manhattan-us-attorney-and-dea-announce-charges-against-rochester-drug-cooperative-and; see also CRS Legal Sidebar LSB10307, Corporate Drug Trafficking Liability—a New Legal Front in

the Opioid Crisis, by Joanna R. Lampe (2019). In 2022, a federal jury convicted the company’s former CEO of

conspiring to distribute unlawfully oxycodone and fentanyl and conspiring to defraud DEA. Press Release, DOJ,

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executives at the pharmaceutical distributor Miami-Luken, Inc., among others, for conspiracy to

violate the CSA’s trafficking provisions.213

Violations of the CSA’s trafficking provisions are criminal offenses that may give rise to large

fines and significant prison time. Penalties vary according to the offense and may further vary

based on the type and amount of the controlled substance at issue. Unauthorized simple

possession of a controlled substance may prompt a minimum fine of $1,000 and a term of up to a

year in prison.214 Distribution of large quantities of certain drugs—including specific Schedule I

controlled substances such as heroin and LSD and specific Schedule II controlled substances such

as cocaine and methamphetamine—carries a prison sentence of 10 years to life and a fine of up to

$10 million for an individual or a fine of up to $50 million for an organization.215 Penalties

increase for second or subsequent offenses, or if death or serious bodily injury results from the

use of the controlled substance.216 Compared with the civil penalties available for violations of

the CSA’s registration provisions, the Act’s criminal trafficking provisions generally entail greater

potential liability—particularly for individual defendants—but also require prosecutors to show

that a violation was intentional.217

The CSA is not the only means to target misconduct related to the distribution of pharmaceutical

and non-pharmaceutical controlled substances. Rather, such conduct can give rise to liability

under numerous other provisions of federal and state law. For example, drug companies may face

administrative sanctions or criminal charges under the FD&C Act.218 Companies and individuals

may also be subject to federal criminal charges under the Racketeer Influenced and Corrupt

Organizations Act219 or the Federal Anti-Kickback Statute.220 Those statutes notably formed part

of the basis for the significant settlement between DOJ and opioid manufacturer Purdue Pharma

Laurence Doud, Former CEO of Pharmaceutical Distributor, Convicted of Conspiring to Distribute Controlled

Substances and Defrauding the DEA (Feb. 2, 2022), https://www.justice.gov/usao-sdny/pr/laurence-doud-former-ceopharmaceutical-distributor-convicted-conspiring-distribute.

213 See Indictment, United States v. Rattini, No. 19-cr-00081 (S.D. Ohio July 17, 2019). DOJ dropped the charges

against Miami-Luken and its executives following the Supreme Court’s decision in Ruan. See Order Granting Mot.

Dismiss, United States v. Rattini, No. 19-cr-00081 (S.D. Ohio Aug. 11, 2022).

214 21 U.S.C. § 844(a).

215 Id. § 841(b)(1)(A).

216 Id. § 841(b).

217 A civil violation of the CSA’s recordkeeping and reporting requirements requires only a showing of negligence. See

21 U.S.C. § 842(a)(5). A violation of § 842 may be a crime punishable by a fine and not more than a year in prison if

“prosecuted by an information or indictment which alleges that the violation was committed knowingly and the trier of

fact specifically finds that the violation was so committed.” Id. § 842(c)(2)(A). A violation of the CSA’s trafficking

provisions must be committed “knowingly or intentionally,” with corporations subject to liability “based on the

‘knowledge and intent’ of their employees.” United States v. Philip Morris USA Inc., 566 F.3d 1095, 1118 (D.C. Cir.

2009); see also 21 U.S.C. § 841.

218 See, e.g., id. § 333; see also CRS Report R43609, Enforcement of the Food, Drug, and Cosmetic Act: Select Legal

Issues, by Jennifer A. Staman (2018).

219 Racketeer Influenced and Corrupt Organizations Act (RICO), Pub. L. No. 90-452, tit. IX, § 901(a), 84 Stat. 941.

See, e.g., Press Release, DOJ, Founder and Owner of Pharmaceutical Company Insys Arrested and Charged with

Racketeering (Oct. 26, 2017), https://www.justice.gov/opa/pr/founder-and-owner-pharmaceutical-company-insysarrested-and-charged-racketeering; Gabrielle Emmanuel and Katie Thomas, Opioid Company Executives Convicted of

Racketeering, N.Y. TIMES, May 3, 2019, at B1.

220 See, e.g., Press Release, DOJ, Justice Department Announces Global Resolution of Criminal and Civil

Investigations with Opioid Manufacturer Purdue Pharma and Civil Settlement with Members of the Sackler Family

(Oct. 21, 2020), https://www.justice.gov/opa/pr/justice-department-announces-global-resolution-criminal-and-civilinvestigations-opioid.

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in 2020.221 And manufacturers and distributors of opioids have faced numerous civil suits under

federal and state law based on the companies’ marketing and distribution of prescription

opioids.222

Legal Considerations for the 119th Congress

Controlled substances regulation has received significant attention from Congress in recent years.

Policymakers have confronted a growing divergence between the status of marijuana under state

and federal law and considered whether and how to facilitate clinical research involving Schedule

I controlled substances. In addition, the opioid epidemic and various federal, state, and local

efforts to respond to the crisis have raised a number of legal and policy questions, including how

to regulate synthetic opioids related to fentanyl and whether to control xylazine, a veterinary drug

that is sometimes misused by humans either alone or in combination with opioids.

Federal and State Marijuana Regulation

One topic that raised a number of legal considerations for the 118th Congress is the increasing

divergence between federal and state marijuana regulation.223 The CDC reports that as of

February 2024, 24 states, three territories, and the District of Columbia have passed laws

removing prohibitions on medical and recreational marijuana use by adults age 21 or older.224

Thirty-eight states, three territories, and D.C. have passed laws permitting medical use of

marijuana; another nine states authorize medical use of cannabis derivatives, such as cannabidiol

(CBD), that contain low levels of tetrahydrocannabinol (THC).225 However, marijuana is a

Schedule I controlled substance under federal law, and state marijuana legislation has no effect on

that status.226

221 See id. DOJ, PLEA AGREEMENT WITH PURDUE PHARMA L.P. (Oct. 20, 2020), https://www.justice.gov/opa/press-

release/file/1329576/dl (Purdue Pharma LP pled guilty to violating the Federal Anti-Kickback Statute and conspiracy to

defraud the United States); see DOJ, PURDUE PHARMA L.P. SETTLEMENT AGREEMENT (Oct 21, 2020),

https://www.justice.gov/opa/press-release/file/1329571/dl, and DOJ, SACKLER SETTLEMENT AGREEMENT (Oct 21,

2020), https://www.justice.gov/opa/press-release/file/1329736/dl (the company and its shareholders also settled civil

claims brought by the United States).

222 See, e.g., National Prescription Opiate Litigation, No. 17-MD-2804 (N.D. Ohio Dec. 12, 2017); see also CRS Legal

Sidebar LSB10365, Overview of the Opioid Litigation and Related Settlements and Settlement Proposals, by Wen W.

Shen (2019); CRS Legal Sidebar LSB10226, State and Local Governments Pursue Judicial Solutions to the Opioid

Epidemic, by Jennifer A. Staman (2018).

223 See generally CRS Report R44782, The Evolution of Marijuana as a Controlled Substance and the Federal-State

Policy Gap, coordinated by Lisa N. Sacco (2022).

224 See CDC, State Medical Cannabis Laws (Feb. 16, 2024), https://www.cdc.gov/cannabis/about/state-medicalcannabis-laws.html.

225 Id. The Commonwealth of the Northern Mariana Islands has generally legalized marijuana regardless of whether it

is for medical or recreational use and does not have a regulatory program specific to medical marijuana. The CDC

therefore does not include the Northern Marianas in its list of jurisdictions that have legalized medical marijuana. Id.

226 See, e.g., Gonzales v. Raich, 545 U.S. 1, 29 (2004). See also CRS Legal Sidebar LSB10482, State Marijuana

“Legalization” and Federal Drug Law: A Brief Overview for Congress, by Joanna R. Lampe (2024). Notably,

however, CBD is not subject to the CSA. The 2018 Farm Bill exempted “hemp”—cannabis and cannabis derivatives

containing very low levels of THC—from control under the CSA. See 21 U.S.C. § 802(16)(B)(i). Accordingly, CBD

products that meet those requirements are no longer a federally controlled substance. CBD remains subject to federal

regulation under the FD&C Act, and FDA has taken the position that CBD is a drug that may not lawfully added to

foods or marketed as a dietary supplement. See Press Release, FDA, Statement from FDA Commissioner Scott

Gottlieb, M.D., on Signing of the Agriculture Improvement Act and the Agency’s Regulation of Products Containing

Cannabis and Cannabis-Derived Compounds (Dec. 20, 2018), https://www.fda.gov/news-events/press(continued...)

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As discussed below, certain legal and practical considerations limit federal prosecutions of

individuals and businesses involved in the state-legal marijuana industry.227 However, regardless

of whether they are subject to criminal prosecution, marijuana users and participants in the statelegal marijuana industry may face collateral consequences arising from the federal prohibition of

marijuana. Various federal laws impose legal consequences based on criminal activity, including

violations of the CSA. For example, even if authorized under state law, marijuana businesses may

be unable to access banking services due to federal anti-money laundering laws,228 and those

businesses may be ineligible for certain federal tax deductions.229 The involvement of income

from a marijuana-related business may also prevent a bankruptcy court from approving a

bankruptcy plan.230 For individuals, some CSA violations involving marijuana may have adverse

immigration consequences.231 Illicit drug use or convictions may limit individuals’ eligibility for

federal student financial aid and other benefits.232 Federal law prohibits the possession of firearms

or ammunition by any person who is “an unlawful user of or addicted to any controlled

announcements/statement-fda-commissioner-scott-gottlieb-md-signing-agriculture-improvement-act-and-agencys; see

also Sean M. O’Connor & Erika Lietzan, The Surprising Reach of FDA Regulation of Cannabis, Even After

Descheduling, 68 AM. U. L. REV. 823 (2019); CRS In Focus IF11250, FDA Regulation of Cannabidiol (CBD)

Consumer Products, by Agata Bodie and Renée Johnson (2020).

227 See infra “Appropriations Limitations.”

228 Anti-money laundering laws prohibit, inter alia, “conduct[ing] or attempt[ing] to conduct ... a financial transaction

which in fact involves the proceeds of specified unlawful activity ... with the intent to promote the carrying on of

specified unlawful activity” 18 U.S.C. §§ 1956(a). For a full list of predicate offenses, see the “Specified Unlawful

Activities” section of CRS Report RL33315, Money Laundering: An Overview of 18 U.S.C. § 1956 and Related

Federal Criminal Law, by Charles Doyle (2017). For further discussion of banking law issues related to the marijuana

policy gap, see the “Federal Financial Laws and Financial Services for Marijuana Businesses” section of CRS Report

R44782, The Evolution of Marijuana as a Controlled Substance and the Federal-State Policy Gap, coordinated by Lisa

N. Sacco (2022).

229 See 26 U.S.C. § 280E (“No deduction or credit shall be allowed for any amount paid or incurred during the taxable

year in carrying on any trade or business if such trade or business (or the activities which comprise such trade or

business) consists of trafficking in controlled substances (within the meaning of schedule I and II of the Controlled

Substances Act) which is prohibited by Federal law or the law of any State in which such trade or business is

conducted.”). See generally CRS Report R46709, The Application of Internal Revenue Code Section 280E to

Marijuana Businesses: Selected Legal Issues, by Milan N. Ball (2021).

230 A court may not confirm a bankruptcy plan “proposed ... by any means forbidden by law.” 11 U.S.C. § 1129(a).

Courts have split on how that provision applies to cannabis-related businesses. Compare Garvin v. Cook Investments

NW, SPNWY, LLC, 922 F.3d 1031, 1033 (9th Cir. 2019) (concluding that bankruptcy plan involving leased property

used to grow marijuana was not proposed “by any means forbidden by law”), with In re Rent-Rite Super Kegs W. Ltd.,

484 B.R. 799, 809 (Bankr. D. Colo. 2012) (dismissing bankruptcy case where the debtor derived roughly 25% of its

revenues from leasing warehouse space to tenants who grew marijuana because “a significant portion of the Debtor’s

income is derived from an illegal activity”) (footnote omitted); In re Basrah Custom Design, Inc., 600 B.R. 368 (Bankr.

E.D. Mich. 2019) (dismissing bankruptcy case where the court determined that the debtor sought “to enable its owner

to profit from a marijuana business” that violated the CSA).

231 See 8 U.S.C. § 1427(a) (providing that no person shall be naturalized unless that person, among other things, “has

been and still is a person of good moral character”); 8 C.F.R. § 316.10(b)(2) (2024) (“An applicant shall be found to

lack good moral character if during the statutory period the applicant ... [v]iolated any law of the United States, any

State, or any foreign country relating to a controlled substance, provided that the violation was not a single offense for

simple possession of 30 grams or less of marijuana”).

232 See CRS Legal Sidebar LSB10556, The MORE Act: House Plans Historic Vote on Federal Marijuana Legalization,

by Joanna R. Lampe (2020); CRS Report R42394, Drug Testing and Crime-Related Restrictions in TANF, SNAP, and

Housing Assistance, by Maggie McCarty et al. (2016).

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substance.”233 Furthermore, people who use marijuana, even for medical purposes, generally

enjoy little or no legal protection from adverse employment consequences.234

Federal laws other than the CSA may limit states’ discretion in enacting marijuana laws. For

instance, some provisions of state medical marijuana laws have been challenged under the

Constitution’s Dormant Commerce Clause, which prohibits states from enacting laws that

discriminate against or unduly burden interstate commerce.235

Appropriations Limitations

Congress has addressed the divergence between federal and state marijuana law in part by

limiting enforcement of the CSA against certain state-legal activities related to medical

marijuana. In each budget cycle since FY2015, Congress has passed an appropriations rider

prohibiting DOJ from using taxpayer funds to prevent the states from “implementing their own

laws that authorize the use, distribution, possession, or cultivation of medical marijuana.”236 The

current appropriations rider is in effect through March 14, 2025.237

On its face, the appropriations rider bars DOJ from taking legal action against the states directly

to prevent them from promulgating or enforcing medical marijuana laws. In addition, federal

courts have held that the rider prohibits certain federal prosecutions of private individuals or

organizations that produce, distribute, or possess marijuana in accordance with state medical

marijuana laws. Criminal defendants have invoked the rider before trial, seeking either the

dismissal of their indictments or injunctions barring prosecution.238

Following a decision of the Ninth Circuit in the 2016 case United States v. McIntosh, several

federal courts have interpreted the appropriations rider to bar DOJ from expending any

appropriated funds to prosecute activities involving medical marijuana that are conducted in

“strict compliance” with state law.239 For example, in one 2019 case, the Ninth Circuit upheld the

prosecution of two individuals involved in the production of medical marijuana who smoked

233 18 U.S.C. § 922.

234 See Kathryn Evans, What Legal Protections Exist for Employees who Use Medical Marijuana?, NAT’L LAW REV.

(Oct. 21, 2020), https://www.natlawreview.com/article/what-legal-protections-exist-employees-who-use-medicalmarijuana.

235 Compare Northeast Patients Grp. v. United Cannabis Patients and Caregivers of Maine, 45 F.4th 542 (1st Cir. 2022)

(holding that the Maine Medical Marijuana Act’s residency requirement violates the dormant Commerce Clause) with

Jensen v. Md. Cannabis Admin., 719 F. Supp. 3d 466 (D. Md. 2024) (“join[ing] with those courts across the country

that have found that the dormant Commerce Clause does not apply to state recreational cannabis laws”). See also Cong.

Rsch. Serv., Overview of Dormant Commerce Clause, CONSTITUTION ANNOTATED,

https://constitution.congress.gov/browse/essay/artI-S8-C3-7-1/ALDE_00013307/ (last visited Jan. 13, 2025).

236 Consolidated Appropriations Act, 2024, Pub. L. No. 118-42, div. C, § 531, 138 Stat. 25, 174 (2024). The

appropriations rider is sometimes known as the “Rohrabacher-Farr Amendment” or the “Rohrabacher-Blumenauer

Amendment.” See, e.g., United States v. Sirois, 119 F. 4th 143, 146 & n.1. The rider enumerates the specific states and

territories to which it applies. The list excludes the three states that have not decriminalized medical marijuana use.

237American Relief Act, 2025, Pub. L. 118-158, div. A, § 101 (Dec. 21, 2024).

238 By contrast, courts have generally declined to apply the rider outside the context of initial criminal prosecutions. For

instance, the Ninth Circuit has held that the provision does not “impact[ ] the ability of a federal district court to restrict

the use of medical marijuana as a condition of probation.” United States v. Nixon, 839 F.3d 885, 886 (2016). In a 2024

decision, the U.S. Court of Appeals for the Eighth Circuit assumed that the rider might bar revocation of supervised

release in some circumstances, but held that it did not apply to the case at bar because the challenger “engaged in

unlawful conduct, even under Iowa’s medical-marijuana regime.” United States v. Doolin, 93 F.4th 1094, 1096 (2024).

239 United States v. McIntosh, 833 F.3d 1163, 1178 (9th Cir. 2016); see also Duval v. United States, 372 F. Supp. 3d

544, 555–56 (E.D. Mich. 2019); Sandusky v. Goetz, No. 18-CV-01436-GPG, 2018 WL 6505803, at *4–5 (D. Colo.

Dec. 11, 2018), rev’d and remanded, 944 F.3d 1240 (10th Cir. 2019); U.S. v. Jackson, 388 F. Supp. 3d 505, 506–08

(E.D. Pa. 2019).

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marijuana as they processed plants for sale.240 Although state law permitted medical marijuana

use by “qualifying patients,” the court concluded that the defendants failed to show they were

qualifying patients, and thus they could be prosecuted because their personal marijuana use did

not strictly comply with state medical marijuana law.241

More recently, in the 2022 case United States v. Bilodeau, the U.S Court of Appeals for the First

Circuit (First Circuit) declined to follow the Ninth Circuit and held that the rider also bars

prosecution in some cases where defendants did not strictly comply with state medical marijuana

law.242 The First Circuit noted that the text of the rider does not explicitly require strict

compliance with state law and that, given the complexity of state marijuana regulations, “the

potential for technical noncompliance [with state law] is real enough that no person through any

reasonable effort could always assure strict compliance.”243 Thus, the First Circuit concluded that

requiring strict compliance with state law would likely chill state-legal medical marijuana

activities and prevent the states from giving effect to their medical marijuana laws.244 However,

the court also rejected the defendants’ argument that the rider “must be read to preclude the DOJ,

under most circumstances, from prosecuting persons who possess state licenses to partake in

medical marijuana activity.”245 Ultimately, the First Circuit held that the rider bars CSA

prosecution in at least some cases where the defendant has committed minor technical violations

of state medical marijuana laws, but it declined to “fully define [the] precise boundaries” of its

alternative standard.246

In November 2024, the First Circuit issued another decision applying the medical marijuana

appropriations rider. In United States v. Sirois, two criminal defendants argued that the rider

should bar their prosecutions because they were in “substantial compliance” with state medical

marijuana law.247 The government did not contest the substantial compliance standard.248

Applying that standard, the court held that the prosecutions could go forward because the

defendants failed to show by a preponderance of the evidence that they were in substantial

compliance with state law.249

It remains to be seen whether and how the differences in reasoning between the Ninth Circuit and

the First Circuit will make a practical difference in federal marijuana prosecutions.250 Congress

240 United States v. Evans, 929 F.3d 1073, 1076–79 (9th Cir. 2019). See also United States v. Kleinman, 880 F.3d 1020,

1027–30 (9th Cir. 2017) (prosecution was proper because sales of marijuana to out-of-state customers violated state

law); United Sates v. Bloomquist, 361 F. Supp. 3d 744, 749–51 (W.D. Mich. 2019) (same, where defendant violated

state law by possessing excessive amounts of marijuana and selling marijuana to someone who was not allowed to use

medical marijuana).

241 Evans, 929 F.3d at 1078–79 (9th Cir. 2019).

242 24 F.4th 705 (2022).

243 Id. at 713.

244 Id. at 713–14.

245 Id. at 714.

246 Id. at 715. On the record before it, the court concluded that “the defendants’ cultivation, possession, and distribution

of marijuana aimed at supplying persons whom no defendant ever thought were qualifying patients under Maine law”

and that a CSA conviction in those circumstances would not “prevent Maine’s medical marijuana laws from having

their intended practical effect.” Id.

247 119 F.4th 143, 152 (1st Cir. 2024).

248 Id.

249 Id. at 153.

250 In theory, the First Circuit’s analysis could make it easier for defendants to invoke the appropriations rider to bar

federal prosecutions, because they could do so even if they had not been in strict compliance with state law. In practice,

however, resource limitations and enforcement priorities have historically meant that federal marijuana prosecutions

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has the power to enact legislation adopting its preferred interpretation of the rider or otherwise

clarifying its scope. Congress could also expand the scope of the rider to bar prosecution of other

state-legal activities involving marijuana251 or limit or repeal the rider.

Executive Branch Policy and Simple Possession Pardon

Notwithstanding the appropriations rider, activities that fall outside the scope of state medical

marijuana laws remain potentially subject to federal prosecution. This includes all state-legal

activities involving recreational marijuana. As a practical matter, DOJ typically has not

prosecuted individuals who possess marijuana for personal use on private property but instead has

“left such lower-level or localized marijuana activity to state and local authorities through

enforcement of their own drug laws.”252 DOJ issued guidance in 2018 reaffirming the authority of

federal prosecutors to exercise prosecutorial discretion to target federal marijuana offenses “in

accordance with all applicable laws, regulations, and appropriations.”253 In recent years, DOJ has

pursued marijuana prosecutions in the context of large-scale trafficking operations or gang-related

activity.254 The Biden Administration DOJ did not issue formal guidance on marijuana policy, but

Attorney General Merrick Garland indicated that the agency would not prioritize prosecuting

individuals for personal use of marijuana.255

On October 6, 2022, President Biden issued a proclamation granting “a full, complete, and

unconditional pardon” to “all current United States citizens and lawful permanent residents” who

had committed or been convicted of simple possession of marijuana under the CSA or a related

provision of the D.C. Code.256 On December 22, 2023, President Biden issued an additional

pardon to all current U.S. citizens and lawful permanent residents who had committed or been

target individuals and organizations that clearly have not complied with state medical marijuana law. Thus, one of the

First Circuit judges who considered Bilodeau agreed with the panel’s interpretation of the rider but wrote a concurrence

noting that, in practice, the First Circuit’s standard might not be “materially different from the one that the Ninth

Circuit applied.” Bilodeau, 24 F.4th at 718 (Barron, J., concurring).

251 See, e.g., State Cannabis Commerce Act, H.R. 3546, 116th Cong. (2019); State Cannabis Commerce Act, S. 2030,

116th Cong. (2019); cf. STATES 2.0 Act, H.R. 6673, 118th Cong. (2023) (would have amended the CSA so that,

subject to certain exceptions, it “shall not apply” to marijuana-related activities that comply with state law); STATES

Act, H.R. 2093, 116th Cong. (2019); STATES Act, S. 1028, 116th Cong. (2019).

252 U.S. GOV’T ACCOUNTABILITY OFF., GAO-16-1, STATE MARIJUANA LEGALIZATION: DOJ SHOULD DOCUMENT ITS

APPROACH TO MONITORING THE EFFECTS OF LEGALIZATION 9 (2015).

253 Memorandum from Jefferson B. Sessions, Attorney Gen., U.S. DOJ, to all U.S. Attorneys, on Marijuana

Enforcement (Jan. 4, 2018), https://www.justice.gov/opa/press-release/file/1022196/download.

254 See, e.g., Press Release, DOJ, DEA Investigation in Chapel Hill Area Uncovers Large-Scale Drug Ring (Dec. 17,

2020), https://www.justice.gov/usao-mdnc/pr/dea-investigation-chapel-hill-area-uncovers-large-scale-drug-ring; Press

Release, DOJ, Pittsburgh-area Man Sentenced for Supplying SCO Gang with Drugs (Jan. 21, 2021),

https://www.justice.gov/usao-wdpa/pr/pittsburgh-area-man-sentenced-supplying-sco-gang-drugs; Press Release, DOJ,

Indictment Charges Bridgeport Gang Members with Drug Trafficking, Committing 4 Murders (Jan. 22, 2021),

https://www.justice.gov/usao-ct/pr/indictment-charges-bridgeport-gang-members-drug-trafficking-committing-4murders.

255 See, e.g., A Review of the President’s Fiscal Year 2023 Funding Request for the U.S. Department of Justice:

Hearing Before the Sen. Appropriations Subcommittee on Commerce, Justice, Science, and Related Agencies, 117th

Cong. (2022) (testimony of Att’y. Gen. Merrick B. Garland) (“I think I laid this out actually also in my confirmation

hearing and my view hasn’t really changed since then, and that is that the Justice Department has almost never

prosecuted use of marijuana and that’s not an efficient use of the resources given the opioid and methamphetamine

epidemic that we have.”).

256 Proclamation No. 10467, 87 Fed. Reg. 61441 (Oct. 6, 2022).

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convicted of “the offense of simple possession of marijuana, attempted simple possession of

marijuana, or use of marijuana” under the CSA, the D.C. Code, or related federal regulations.257

President Biden’s invocations of the clemency power mean that people who committed simple

possession or use of marijuana or attempted to commit those offenses before the issuance of the

proclamations may not be prosecuted or punished for the offenses under the relevant provisions

of the CSA or the D.C. Code.258

Several factors limit the scope of the pardons. First, they apply only to violations of federal and

D.C. law and do not affect other state law marijuana offenses, because the President has no direct

power to change state law or compel the states to adopt federal policies.259 Second, the pardons

apply only to simple possession of marijuana and related low-level offenses, which the federal

government rarely prosecutes.260 They do not apply to other marijuana-related CSA offenses such

as manufacture, distribution, or possession with intent to distribute or to other federal crimes.261

Third, the pardons by their terms do not apply to “individuals who were non-citizens not lawfully

present in the United States at the time of their offense.”262 Fourth, the pardons apply only to

257 Proclamation No. 10688, 88 Fed. Reg 90083 (Dec. 28, 2023). On January 17, 2025, President Biden commuted the

sentences of nearly 2,500 individuals who had been convicted of non-violent drug offenses. That grant of clemency

was not limited to marijuana offenders and applied to “individuals who received lengthy sentences based on discredited

distinctions between crack and powder cocaine, as well as outdated sentencing enhancements for drug crimes.”

Statement from President Joe Biden on Additional Clemency Actions (Jan. 17, 2025),

https://www.whitehouse.gov/briefing-room/statements-releases/2025/01/17/statement-from-president-joe-biden-onadditional-clemency-actions/.

258 Although the District of Columbia has its own criminal code, its criminal justice system has some overlap with the

federal system and is subject to the President’s clemency power. For additional information on the President’s

clemency power, see CRS Report R46179, Presidential Pardons: Overview and Selected Legal Issues, by Michael A.

Foster (2020).

259 See id. “Constraints on the Pardon Power.” In announcing the pardon, President Biden also encouraged state

governors to grant clemency for state offenses. While some governors have taken such steps or expressed willingness

to do so, in some states, governors cannot independently grant clemency. See, e.g., David Montgomery, Governors

Split on Biden’s Call to Pardon Low-Level Pot Offenders, PEW (Oct. 28, 2022), https://www.pewtrusts.org/en/researchand-analysis/blogs/stateline/2022/10/28/governors-split-on-bidens-call-to-pardon-low-level-pot-offenders. The pardon

also does not apply to offenses under the Uniform Code of Military Justice. See, e.g., Michael Lee, Biden’s Pardon of

Marijuana Offenses Won’t Apply to Military, FOX NEWS (Oct. 9, 2022), https://www.foxnews.com/politics/bidenspardons-marijuana-offenses-wont-apply-military.

260 The U.S. Sentencing Commission (USSC) reports that about 7,700 people subject to the pardon were convicted of

only simple possession since FY1992, none of whom were in federal custody at the time of the grant of clemency.

USSC, NUMBER OF FEDERAL OFFENDERS CONVICTED ONLY OF 21 U.S.C. § 844 INVOLVING MARIJUANA, FISCAL YEARS

1992 – 2021 (Oct. 12, 2022), https://www.ussc.gov/sites/default/files/pdf/news/press-releases-and-newsadvisories/news-advisories/20221012_Updated-News-Advisory-Data-Analysis.pdf. In FY2021, 117 people subject to

the pardon were convicted of only simple possession. See id. Additional individuals convicted of simple possession

were not subject to the pardon. See USSC, WEIGHING THE CHARGES: SIMPLE POSSESSION OF DRUGS IN THE FEDERAL

CRIMINAL JUSTICE SYSTEM 6 (Sept. 2016), https://www.ussc.gov/sites/default/files/pdf/research-andpublications/research-publications/2016/201609_Simple-Possession.pdf.

261 The USSC reports that 425 people were convicted of possessing marijuana and possessing other illicit drugs, USSC,

NUMBER OF FEDERAL OFFENDERS, supra note 259. In addition, 585 people were convicted of simple possession of

marijuana and one or more other crimes. USSC, NUMBER OF FEDERAL OFFENDERS, supra note 259. Those people would

remain liable for the other offenses. After the pardon was announced, the USSC issued policy priorities including

“consideration of possible amendments to the [Sentencing] Guidelines Manual relating to criminal history to address ...

the impact of simple possession of marihuana offenses.” Final Priorities for Amendment Cycle, 87 Fed. Reg. 67756,

67756 (Nov. 9, 2022).

262According to a 2016 USSC report, the vast majority of federal marijuana possession arrests occur at the border

between the United States and Mexico and involve non-citizens. See USSC, WEIGHING THE CHARGES, supra note 259,

at 5–6. Among offenders sentenced for marijuana possession in FY2013, over 94% of those arrested at the border were

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offenses committed before the proclamations.263 Thus, while DOJ is currently not prioritizing

prosecuting low-level marijuana offenses, the October 2022 and December 2023 pardons do not

prevent prosecution of future offenses if the current Administration or a future Administration

adopts a different policy. Fifth, the pardons may not remove all legal consequences of marijuana

possession, because they do not expunge convictions.264 Moreover, some collateral consequences

of marijuana-related activities do not depend on a person being charged with or convicted of a

CSA violation.265

In addition, and most fundamentally, the pardons did not change the status of marijuana under

federal law. The President lacks the power to make such a change unilaterally.266 In announcing

the first grant of clemency, President Biden directed the Attorney General to review the

classification of marijuana under the CSA.267 DOJ subsequently announced a proposal to

reschedule marijuana, which is discussed further below.268

It remains to be seen what approach President Trump’s second Administration will take toward

marijuana regulation. During President Trump’s first Administration, DOJ rescinded Obama

Administration guidance deprioritizing enforcement against low-level marijuana offenses.269

Nonetheless, the number of DEA marijuana arrests fell every year during the first Trump

Administration.270

DOJ Proposal to Reschedule Marijuana

On May 21, 2024, DOJ published in the Federal Register a notice of proposed rulemaking

(NPRM) proposing to move marijuana from Schedule I to Schedule III.271 The agency held an

initial public hearing on the proposal in December 2024.272 As of the date of publication of this

report, it is unknown whether DOJ will finalize the proposal and, if so, what controls the agency

would impose on marijuana.273

not U.S. citizens. Id. at 6. To the extent those individuals were not lawfully present in the country, they would not

benefit from the pardon.

263 The Supreme Court has explained that the President may issue a pardon “at any time after [an offense’s]

commission, either before legal proceedings are taken, or during their pendency, or after conviction and judgment.” Ex

parte Garland, 71 U.S. 333, 380 (1866).

264 See DOJ, Office of the Pardon Attorney, Presidential Proclamation on Marijuana Possession, Attempted

Possession, and Use (December 16, 2024), https://www.justice.gov/pardon/presidential-proclamation-marijuanapossession.

265 See supra “Enforcement and Penalties.”

266 See CRS Legal Sidebar LSB10655, Does the President Have the Power to Legalize Marijuana?, by Joanna R.

Lampe (2021).

267 Proclamation No. 10467, 87 Fed. Reg. 61441 (Oct. 6, 2022).

268 See infra “DOJ Proposal to Reschedule Marijuana.”

269 Jefferson B. Sessions, supra note 253.

270 See DOJ, FEDERAL JUSTICE STATISTICS, 2022 (Jan. 2024), https://bjs.ojp.gov/document/fjs22.pdf.

271 Schedules of Controlled Substances: Rescheduling of Marijuana, 89 Fed. Reg. 44597 (proposed May 21, 2024).

While scheduling is generally initiated by DEA, the marijuana NPRM indicated that DOJ was initiating the process and

at times included views of both DEA and DOJ. See, e.g., id. at 44601.

272DEA to Hold Hearing on the Rescheduling of Marijuana, DEA (Nov. 26, 2024),

https://www.dea.gov/stories/2024/2024-11/2024-11-26/dea-hold-hearing-rescheduling-marijuana.

273 The NPRM indicated that DOJ might place marijuana in Schedule III while also posing additional, substancespecific controls as required to comply with the United States’ international treaty obligation. See Schedules of

Controlled Substances: Rescheduling of Marijuana, 89 Fed. Reg. 44597, 44620 (proposed May 21, 2024).

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Moving marijuana from Schedule I to Schedule III, without other legal changes, would not bring

the state-legal medical or recreational marijuana industry into compliance with federal controlled

substances law. With respect to medical marijuana, a key difference between placement in

Schedule I and placement in Schedule III is that substances in Schedule III have an accepted

medical use and may lawfully be dispensed by prescription, while substances in Schedule I

cannot.274 However, prescription drugs must be approved by FDA. Although FDA has approved

some drugs derived from or related to cannabis, marijuana itself is not an FDA-approved drug.275

Moreover, if one or more marijuana products obtained FDA approval, manufacturers and

distributors would need to register with DEA and comply with regulatory requirements that apply

to Schedule III controlled substances in order to handle those products.276 Users of medical

marijuana would need to obtain valid prescriptions for the substance from medical providers,

subject to federal legal requirements that differ from existing state regulatory requirements for

medical marijuana.277

Rescheduling marijuana would not affect the medical marijuana appropriations rider discussed

above.278 Thus, so long as the current rider remains in effect, participants in the state-legal

medical marijuana industry who comply with state law would be shielded from federal

prosecution. If the rider were to lapse or be repealed, these persons would again be subject to

prosecution at the discretion of DOJ. With respect to the manufacture, distribution, and

possession of recreational marijuana, if marijuana were moved to Schedule III, such activities

would remain illegal under federal law and potentially subject to federal prosecution regardless of

their status under state law.

Some criminal penalties for CSA violations depend on the schedule in which a substance is

classified.279 If marijuana were moved to Schedule III, applicable penalties for some offenses

would be reduced.280 By contrast, some CSA penalties apply to activities involving marijuana

specifically, including certain quantity-based mandatory minimum sentences.281 Those substancespecific penalties would not change as a result of rescheduling. Similarly, the Medical Marijuana

and Cannabidiol Research Expansion Act imposed some registration requirements related to

research that apply specifically to marijuana.282 Those requirements would not change if

marijuana were rescheduled.

One significant legal change if marijuana were rescheduled relates to the taxation of marijuanarelated businesses. Section 280E of the Internal Revenue Code prohibits deduction of business

expenses of any trade or business that “consists of trafficking in controlled substances (within the

meaning of schedule I and II of the Controlled Substances Act) which is prohibited by Federal

law or the law of any State in which such trade or business is conducted.”283 As the provision

applies only to activities involving substances in Schedule I or II, moving marijuana from

274 See 21 U.S.C. § 829.

275 See FDA and Cannabis: Research and Drug Approval Process, FDA (Feb. 24, 2023), https://www.fda.gov/news-

events/public-health-focus/fda-and-cannabis-research-and-drug-approval-process.

276 See supra “Registration Requirements.”

277 See 21 U.S.C. § 829.

278 See supra “Appropriations Limitations.”

279 See, e.g., 21 U.S.C. § 841(b)(1)(C).

280 See id. A criminal prohibition on advertising Schedule I controlled substances would cease to apply to marijuana if

it were moved to Schedule III. See id. § 843(c).

281 See, e.g., id. § 841(b)(1)(A).

282 Pub. L. 117-215, 136 Stat. 2257 (2022).

283 26 U.S.C. § 280E.

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Schedule I to Schedule III would allow marijuana businesses to deduct business expenses on

federal tax filings. Another change is that DEA would no longer need to set annual quotas for the

manufacture of marijuana, because the CSA does not require the agency to set annual production

quotas for Schedule III controlled substances.284 Other collateral legal consequences would

continue to attach to unauthorized marijuana-related activities.285

Proposed Marijuana Legislation

Numerous proposals introduced in the 116th-118th Congresses would have changed how the

federal government regulates marijuana. Congress has broad power to regulate marijuana or relax

federal regulation of the substance as part of its authority over interstate commerce.286 As

discussed above, DOJ is currently considering moving marijuana to Schedule III via

administrative rulemaking.287 If Congress wishes to change the legal status of marijuana, it could

do so before or after DOJ makes any final scheduling decision.

Several recent proposals would have removed marijuana from control under the CSA. One highprofile descheduling proposal, the Marijuana Opportunity Reinvestment and Expungement Act

(MORE Act), would have removed marijuana and THC from control under the CSA and required

expungement of past convictions for many federal marijuana offenses.288 Among other things, it

also would have removed some collateral consequences for marijuana-related activities,289

imposed a 5% tax on cannabis products,290 and used revenues from the tax to fund certain grant

programs for disadvantaged individuals and “individuals adversely impacted by the War on

Drugs.”291 The MORE Act passed the House during the 117th Congress but did not pass the

Senate.292

Another descheduling proposal, the Cannabis Administration and Opportunity Act (CAOA),

would have removed from CSA control marijuana and THC derived from the cannabis plant.293 It

also would have provided for expungement of certain past marijuana convictions,294 but it would

have retained federal criminal liability for cannabis-related activities not conducted pursuant to a

federal permit or authorized under the law of the states where they occur.295 In addition, among

other things, it would have provided guidance for regulation of cannabis products under the

284 21 U.S.C. § 826.

285 See discussion supra notes 228–234 and accompanying text.

286 Gonzales v. Raich, 545 U.S. 1, 15 (2004). For background on Congress’s power to regulate interstate commerce, see

Cong. Rsch. Serv., Overview of Commerce Clause, CONSTITUTION ANNOTATED,

https://constitution.congress.gov/browse/essay/artI-S8-C3-1/ALDE_00013403/ (last visited Jan. 13, 2023).

287 See supra “DOJ Proposal to Reschedule Marijuana.”

288 MORE Act, H.R. 5601, §§ 3, 10, 118th Cong. (2023).

289 Id. §§ 7–9.

290 Id. § 5.

291 Id. §§ 5–6.

292 MORE Act, H.R. 3617, 117th Cong. (2021). A previous version of the MORE Act passed the House in December

2020, the first time either chamber of Congress voted on a proposal to decriminalize marijuana. See MORE Act of

2020, H.R. 3884, 116th Cong. (2020), see also Nicholas Wu, House Will Vote on Federal Marijuana Legalization for

the First Time, Bill’s Future in Senate Uncertain, USA TODAY (Sept. 4, 2020)

https://www.usatoday.com/story/news/politics/2020/09/04/marijuana-house-vote-federal-legalization-firsttime/5678068002/.

293 Cannabis Administration and Opportunity Act, S. 4226, § 101, 118th Cong. (2022).

294 Id. § 311.

295 Id. § 112.

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FD&C Act.296 It also would have imposed a 10%-25% tax on cannabis products297 and used

revenues from the tax to fund programs including small business development, community

reinvestment, and opioid abuse treatment.298 Other legislative proposals from the 116th-118th

Congresses would likewise have removed marijuana from control under the CSA.299

Removing marijuana from the coverage of the CSA could raise several legal considerations. First,

by default, the repeal of federal criminal prohibitions rarely applies retroactively.300 To address

this, some descheduling proposals also include provisions designed to address past criminal

convictions related to marijuana.301 Second, removing marijuana from the ambit of the CSA

would not affect other existing statutes and regulations that apply to the drug and thus would not

bring aspects of the existing cannabis industry into compliance with federal laws such as the

FD&C Act.302 Third, Congress might enact new legislation affecting marijuana in conjunction

with any legislation removing it from the scope of the CSA. For instance, legislation introduced

during the 118th Congress would have amended the FD&C Act to provide for the regulation of

cannabis and cannabinoid products.303 Fourth, reducing or removing federal restrictions on

marijuana might be inconsistent with certain treaty obligations of the United States.304 The

296 Id. § 501.

297 Id. § 401.

298 Id. §§ 301–303.

299 See, e.g., States Reform Act of 2023, H.R. 6028, 118th Cong. (2023); Homegrown Act of 2021, H.R. 2649, 117th

Cong. (2021); Common Sense Cannabis Reform for Veterans, Small Businesses, and Medical Professionals Act, H.R.

3105, 117th Cong. (2021); Marijuana Justice Act of 2019, H.R. 1456, 116th Cong. (2019); Marijuana Justice Act of

2019, S. 597, 116th Cong. (2019).

300 See 1 U.S.C. § 109; Hurwitz v. United States, 53 F.2d 552, 552 (D.C. Cir. 1931) (applying then-applicable federal

savings statute to prevent retroactive application of the repeal of a criminal law to a prosecution undertaken before the

repeal); see also S. David Mitchell, In With the Old, Out With the New: Expanding the Scope of Retroactive

Amelioration, 37 AM. J. CRIM. L. 1, 28–38 (2009).

301 In addition to the MORE Act and the CAOA, other legislative proposals from the 117th and 118th Congress would

also have allowed for expungement or sealing of certain federal marijuana convictions. See, e.g., Marijuana

Misdemeanor Expungement Act, H.R. 8917, 118th Cong. (2024); Clean Slate Act of 2021, H.R. 2864, 117th Cong.

(2021). Another proposal sought to facilitate expungement of state convictions. See Harnessing Opportunities by

Pursuing Expungement Act of 2023, H.R. 2677, 118th Cong. (2023). See also, e.g., Marijuana Laws in America:

Racial Justice and the Need for Reform: Hearing Before the House Comm. on the Judiciary, 116th Cong. 12-13 (2019)

(statement of Marilyn J. Mosby).

302 See Press Release, FDA, Statement from FDA Commissioner Scott Gottlieb, M.D., on Signing of the Agriculture

Improvement Act and the Agency’s Regulation of Products Containing Cannabis and Cannabis-Derived Compounds

(Dec. 20, 2018), https://www.fda.gov/news-events/press-announcements/statement-fda-commissioner-scott-gottliebmd-signing-agriculture-improvement-act-and-agencys; see also CRS In Focus IF11250, FDA Regulation of

Cannabidiol (CBD) Consumer Products, by Agata Bodie and Renée Johnson (2020). Congress could also enact

legislation to alter FDA regulation of cannabis-based products. For example, the Legitimate Use of Medicinal

Marihuana Act (LUMMA), H.R. 171, 116th Cong. (2019), would have provided that neither the CSA nor the FD&C

Act “shall prohibit or otherwise restrict” certain activities related to medical marijuana that are legal under state law.

303 Cannabinoid Safety and Regulation Act, S. 5243, 118th Cong. (2024). See also Preparing Regulators Effectively for

a Post-prohibition Adult-use Regulated Environment Act of 2023, H.R. 2598, 118th Cong. (2023); Regulate Marijuana

Like Alcohol Act, H.R. 420, 116th Cong. (2019).

304 See supra “International Treaty Obligations.” The United States is a party to the Single Convention on Narcotic

Drugs, 1961, Mar. 30, 1961, 18 U.S.T. 1407 and the United Nations Convention on Psychotropic Substances, Feb. 21,

1971, 32 U.S.T. 543. Both conventions require parties to impose certain controls on cannabis; however, in December

2020, the United Nations Commission on Narcotic Drugs voted to remove some of the restrictions on cannabis under

the 1961 Convention. See Press Release, United Nations Commission on Narcotic Drugs, CND Votes on

Recommendations for Cannabis and Cannabis-related Substances (Dec. 2, 2020),

https://www.unodc.org/unodc/en/frontpage/2020/December/cnd-votes-on-recommendations-for-cannabis-andcannabis-related-substances.html. Nonetheless, cannabis and its derivatives remain subject to restrictions under the

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applicable treaties are not self-executing,305 meaning that they do not have the same status as

judicially enforceable domestic law.306 However, failure to abide by its treaty obligations could

expose the United States to diplomatic consequences.307

As an alternative to descheduling, some recent proposals would have maintained marijuana as a

controlled substance but moved it to a less restrictive schedule.308 These proposals would

generally move marijuana to Schedule III, as DOJ is currently considering doing by

rulemaking.309 If Congress moved marijuana to Schedule III by legislation, it could

simultaneously consider whether to change some of the legal consequences of the substance’s

Schedule III status. Congress could also legislate to move marijuana to another CSA schedule,

which would subject it to controls more or less stringent than those that apply to Schedule III

controlled substances. As discussed above, moving marijuana to a schedule other than Schedule I

would theoretically allow the substance to be dispensed by prescription for medical purposes.

However, because marijuana is not currently an FDA-approved prescription drug, rescheduling

alone would not allow current state-legal medical recreational marijuana markets to comply with

the CSA.310

Congress could also continue to regulate marijuana as a Schedule I controlled substance while

creating substance-specific exceptions. For instance, several legislative proposals during the

116th-118th Congresses would have left marijuana in Schedule I but limited enforcement of

federal marijuana law in states that have legalized marijuana.311 In the 117th Congress, the Small

international drug control treaties that may be inconsistent with legalization of marijuana, particularly for recreational

purposes. Specifically, cannabis and cannabis resin remain in Schedule I of the 1961 Convention. United Nations

Single Convention on Narcotic Drugs, 1961, List of Drugs Included in Schedule I, Mar. 30, 1961, 18 U.S.T. 1407. The

1961 Convention also contains provisions imposing specific requirements on the cultivation of cannabis. Id. art. 28. In

addition, THC remains subject to control under the 1971 Convention. United Nations Convention on Psychotropic

Substances, List of Substances in Schedule I, Feb. 21, 1971, 32 U.S.T. 543.

305

The Supreme Court has held, “Only ‘[i]f the treaty contains stipulations which are self-executing, that is, require no

legislation to make them operative, [will] they have the force and effect of a legislative enactment.’” Medellin v. Texas,

552 U.S. 491, 505–06 (2008). Congress has made explicit findings that the Convention on Psychotropic Substances “is

not self-executing, and the obligations of the United States thereunder may only be performed pursuant to appropriate

legislation.” 21 U.S.C. § 801a(2). Because the enforcement provisions of the two treaties are similar, with neither

stating that it is self-executing, it appears the Single Convention on Narcotic Drugs also is not self-executing.

306 See Medellin, 552 U.S. at 527 (“A non-self-executing treaty, by definition, is one that was ratified with the

understanding that it is not to have domestic effect of its own force.”). For additional background on the legal effect of

self-executing and non-self-executing treaties, see CRS Report RL32528, International Law and Agreements: Their

Effect upon U.S. Law, by Stephen P. Mulligan (2023).

307 See United Nations Single Convention on Narcotic Drugs, 1961, art. 14, Mar. 30, 1961, 18 U.S.T. 1407 (authorizing

the Narcotics Control Board to recommend to treaty signatories that they stop the export or import of drugs to a

signatory country that violates the treaty, or to publish a report on any matter related to enforcement of the treaty);

United Nations Convention on Psychotropic Substances, art. 19, Feb. 21, 1971, 32 U.S.T. 543 (same). Some

commentators have suggested that it is possible state laws decriminalizing marijuana already conflict with the United

States’ obligations under the treaties. See Brian M. Blumenfeld, Pacta Sunt Servanda State Legislation of Marijuana

and Subnational Violations of International Treaties: A Historical Perspective, 46 PEPP. L. REV. 69, 94–101 (2018);

Jonathan Remy Nash, Doubly Uncooperative Federalism and the Challenge of U.S. Treaty Compliance, 55 COLUM. J.

TRANSNAT’L L. 3, 21–23 (2016).

308 See, e.g., Marijuana 1-to-3 Act of 2021, H.R. 365, 117th Cong. (2012); Legitimate Use of Medicinal Marihuana Act,

H.R. 171, 116th Cong. (2019); Compassionate Access Act, H.R. 715, 115th Cong. (2017).

309 See supra “DOJ Proposal to Reschedule Marijuana.”

310 See id.

311 Strengthening the Tenth Amendment Through Entrusting States 2.0 Act, H.R. 6673, 118th Cong. (2023); State

Cannabis Commerce Act, H.R. 3546, 116th Cong. (2019); S. 2030, 116th Cong. (2019); Strengthening the Tenth

Amendment Through Entrusting States Act (STATES Act), H.R. 2093, 116th Cong. (2019); STATES Act, S. 1028,

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and Homestead Independent Producers Act of 2022 would have allowed shipment of marijuana

within and between states that have legalized the substance.312

Some other recent proposals would have addressed specific legal consequences of marijuana’s

Schedule I status. For example, the SAFE Banking Act,313 a version of which passed the House in

2021,314 sought to protect depository institutions that provide financial services to cannabisrelated businesses from regulatory sanctions. A related bill called the SAFER Banking Act was

introduced in the 118th Congress.315 Other proposals sought to ensure marijuana businesses’

access to insurance and other financial resources,316 facilitate federally approved clinical research

involving marijuana,317 or enable veterans to access information about or use medical

marijuana.318 Additional proposals would have removed collateral legal consequences of

marijuana-related activities for individuals in areas such as immigration,319 gun ownership,320

federal employment,321 and federally assisted housing.322

While most recent proposals would have relaxed federal regulation of marijuana, Congress could

also impose more stringent controls.323 One proposal from the 118th Congress would have

withheld certain federal funds from states in which the purchase or public possession of

marijuana for recreational purposes is lawful.324 A proposal from the 117th Congress would have

prohibited the use of benefits under the Temporary Assistance for Needy Families block grant at

any store that offers marijuana for sale.325 Other proposals sought to address the issues of

marijuana impairment in the workplace326 or driving under the influence of marijuana and other

116th Cong. (2019); Responsibly Addressing the Marijuana Policy Gap Act of 2019, H.R. 1119, 116th Cong. (2019);

Responsibly Addressing the Marijuana Policy Gap Act of 2019 S. 421, 116th Cong. (2019).

312 H.R. 8825, 117th Cong. (2022).

313 SAFE Banking Act of 2023, H.R. 2891, 118th Cong. (2023); SAFE Banking Act of 2023. S. 1323, 118th Cong.

(2023).

314 Secure And Fair Enforcement Banking Act of 2021, H.R. 1996, 117th Cong. (2021).

315 SAFER Banking Act, S. 2860, 118th Cong. (2023).

316 CLAIM Act, H.R. 2984, 118th Cong. (2023), CLAIM Act, S. 1359, 118th Cong. (2023); Ensuring Safe Capital

Access for All Small Businesses Act of 2021, H.R. 2712, 117th Cong. (2021); CLIMB Act, H.R. 8200, 117th Cong.

(2022); see also Ensuring Access to Counseling and Training for All Small Businesses Act of 2019, H.R. 3543, 116th

Cong. (2019).

317 See, e.g., Cannabis Research Act, H.R. 8901, 118th Cong. (2024); Developing and Nationalizing Key Cannabis

Research Act of 2022, H.R. 8540, 117th Cong. (2022); Medical Marijuana Research Act, H.R. 5657, 117th Cong.

(2021). See also infra “Clinical Research and Use of Schedule I Controlled Substances.”

318 See, e.g., Veterans Equal Access Act, H.R. 2431, 118th Cong. (2023); Veterans Medical Marijuana Safe Harbor

Act, H.R. 2682, S. 1204, 118th Cong. (2023); Fully Informed Veteran Act of 2021, H.R. 3601, 117th Cong. (2021);

Veterans Cannabis Use for Safe Healing Act, H.R. 430, 117th Cong. (2021).

319 Destigmatizing in Immigration Act, H.R. 1614, 117th Cong. (2021).

320 Gun Rights And Marijuana Act, H.R. 2772, 118th Cong. (2023).

321 Cannabis Users’ Restoration of Eligibility Act, H.R. 5040. 118th Cong. (2023); see also Intelligence Authorization

Act for Fiscal Year 2024, S. 2103 § 805, 118th Cong. (2023).

322 Marijuana in Federally Assisted Housing Parity Act of 2024, H.R. 7094, 118th Cong. (2024).

323 In addition to the proposals discussed below, see Targeting and Offsetting Existing Illegal Contaminants Act, H.R.

1473, 118th Cong. (2023); Federal Lands Amplified Security for the Homeland (FLASH) Act, H.R. 9678, 118th Cong.

(2024).

324 Stop Pot Act of 2023, H.R. 5323, 118th Cong. (2023).

325 Welfare for Needs not Weed Act, H.R. 4536 117th Cong. (2021). See Personal Responsibility and Work

Opportunity Reconciliation Act of 1996, Pub. L. No. 104-193, tit. I, 110 Stat. 2105, 2110 (commonly referred to as

Temporary Assistance for Needy Families (TANF)).

326 H.R. 8591, 117th Cong. (2022).

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substances.327 Another proposal from the 118th Congress would have provided for congressional

review of DEA rescheduling decisions related to marijuana.328

Clinical Research and Use of Schedule I Controlled Substances

Another issue that received significant attention during the 117th and 118th Congresses was the

possibility that certain Schedule I controlled substances, especially marijuana and psilocybin,

may have medical benefits. As a legal matter, Schedule I status limits researchers’ ability to

conduct clinical research involving these substances and patients’ ability to access such

substances for medical purposes. As substances in Schedule I have no accepted medical use under

the CSA, it is only legal to produce, dispense, and possess those substances in the context of

federally approved scientific studies.329 In addition, federal law limits the use of federal funding

for such research: a rider to the appropriations law for FY2024 provides that no appropriated

funds may be used “for any activity that promotes the legalization of any drug or other substance

included in schedule I” of the CSA, except “when there is significant medical evidence of a

therapeutic advantage to the use of such drug or other substance or … federally sponsored clinical

trials are being conducted to determine therapeutic advantage.”330

Schedule I status under the CSA raises two key legal issues related to medical use and clinical

research. First, some commentators have expressed concerns that the CSA places too many

restrictions on research involving controlled substances, particularly Schedule I controlled

substances that might have a legitimate medical use.331 Barriers to research may make it difficult

both to harness potential medical benefits of those substances and to disprove possible false

claims of benefits that may pose a public health risk.

Second, there is a growing gulf between federal and state law with respect to Schedule I

controlled substances with potential medical benefits. The gap between federal and state

regulation of medical and recreational marijuana is discussed in greater detail above.332 However,

more recently, it appears that a gap may be developing with respect to other Schedule I controlled

substances. On November 3, 2020, voters in Oregon approved a ballot measure authorizing the

use of psilocybin for medical purposes under state law.333 The same day, District of Columbia

327 Drug-Impaired Driving Education Act of 2021, H.R. 3675, 117th Cong. (2021); Impaired Driving Study Act of

2021, H.R. 3253, 117th Cong. (2021).

328 Deferring Executive Authority Act, S. 2909, 118th Cong. (2023).

329 See 21 U.S.C. § 823(g); see also Gonzales v. Raich, 545 U.S. 1, 14 (2004).

330 American Relief Act, 2025, Pub. L. 118-158, div. D, § 509 (Dec. 21, 2024). The provision has been extended

through March 14, 2025. See id., div. A, § 101.

331 See, e.g., Michael H. Andreae, et al., An Ethical Exploration of Barriers to Research on Controlled Drugs, AM. J.

BIOETH. 5–6 (Apr. 2016), https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4849133/pdf/nihms-778176.pdf.

332 See supra “Federal and State Marijuana Regulation.”

333

See Lizzy Acker, Oregon Becomes First State to Legalize Psychedelic Mushrooms, OREGONIAN (Nov. 3, 2020),

https://www.oregonlive.com/politics/2020/11/oregon-becomes-first-state-to-legalize-psychedelic-mushrooms.html.

Through a separate ballot measure, Oregonians voted to decriminalize possession of small amounts of certain Schedule

I and II controlled substances, including cocaine, heroin, oxycodone and methamphetamines. See Cleve R. Wootson Jr.

and Jaclyn Peiser, Oregon Decriminalizes Possession of Hard Drugs, as Four Other States Legalize Recreational

Marijuana, WASH. POST (Nov. 4, 2020), https://www.washingtonpost.com/nation/2020/11/04/election-drugs-oregonnew-jersey/. The ballot measure related to possession of controlled substances was repealed in 2024. See Claire Rush,

Oregon Law Rolling Back Drug Decriminalization Takes Effect, Making Possession a Crime Again, PBS NEWS (Sept.

1, 2024), https://www.pbs.org/newshour/politics/oregon-law-rolling-back-drug-decriminalization-takes-effect-makingpossession-a-crime-again. Psilocybin remains available for medical use in Oregon. See Andrew Jacobs, ‘LifeChanging’ Psychedelics, for When Life Is Ending, N.Y. TIMES (Dec. 17, 2024),

https://www.nytimes.com/2024/12/17/health/psychedelic-medicine-palliative-care-end-of-life.html.

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voters passed a ballot measure deprioritizing the enforcement of criminal prohibitions on certain

psychedelic plants and fungi.334 On November 8, 2022, voters in Colorado approved a ballot

initiative legalizing the use of psilocybin and certain other substances by adults 21 or over and

providing for the establishment of centers for the therapeutic use of psilocybin and psilocyn.335 A

number of cities have also enacted local laws deprioritizing enforcement of controlled substances

offenses involving psychedelics.336 As with state marijuana laws, these changes in D.C., state, and

local law do not alter the status of the affected Schedule I controlled substances under the federal

CSA.337

In recent years, Congress has enacted legislation designed to facilitate research involving

marijuana while also retaining strict controls over the substance. For over 50 years, DEA

registered one farm in the United States to legally produce marijuana for research purposes, and

researchers contended that marijuana from that source was deficient in both quality and

quantity.338 In 2015, Congress passed the Improving Regulatory Transparency for New Medical

Therapies Act, which imposed deadlines on DEA to issue notice of each application to

manufacture Schedule I controlled substances for research and then act on the application.339

Following years of delay and related court challenges,340 DEA published a notice in the Federal

manufacture of marijuana for research purposes.341

In December 2020, DEA issued a final rule governing registration for bulk marijuana

manufacturers.342 The final rule provides that the DEA administrator “may grant an application

for a registration to manufacture marihuana … only if he determines that such registration is

334 See Justin Wm. Moyer, D.C. Voters Approve Ballot Question to Decriminalize Psychedelic Mushrooms, WASH.

POST (Nov. 3, 2020), https://www.washingtonpost.com/local/dc-politics/dc-magic-mushroomsresult/2020/11/03/bb929e86-1abc-11eb-bb35-2dcfdab0a345_story.html. The D.C. ballot measure does not repeal

criminal laws related to psychedelic plants and fungi but rather provides that prosecution for the use and sale of such

substances shall be “among the Metropolitan Police Department’s lowest law enforcement priorities.” Id. The ballot

measure appears to have been tailored to comply with a federal appropriations rider that prohibits the District of

Columbia from expending any federal funds “to enact or carry out any law, rule, or regulation to legalize or otherwise

reduce penalties associated with the possession, use, or distribution of any schedule I substance under the Controlled

Substances Act[.]” Consolidated Appropriations Act, 2020, Pub. L. No. 116-93, tit. VIII, § 809, 133 Stat. 2500 (2019).

The District of Columbia measure is not limited to medicinal use but was motivated in part by the possibility that

psychedelic substances may provide medical benefits. See Justin Wm. Moyer, D.C. Voters to Weigh in on ‘Magic

Mushroom’ Decriminalization After Months-long Campaign, WASH. POST (Oct. 8, 2020),

https://www.washingtonpost.com/local/dc-mushroom-decriminalization/2020/10/08/b19a1a70-0712-11eb-991cbe6ead8c4018_story.html.

335 See Danica Jefferies, Colorado Just Legalized ‘Magic Mushrooms,’ an Idea That’s Growing Nationwide, NBC

NEWS (Nov. 12, 2022), https://www.nbcnews.com/data-graphics/magic-mushrooms-psilocybin-map-colorado-usstates-rcna55980.

336 Psychedelic Legalization & Decriminalization Tracker, PSYCHEDELIC ALPHA,

https://psychedelicalpha.com/data/psychedelic-laws (last visited Jan. 13, 2025).

337 See CRS Legal Sidebar LSB10482, State Marijuana “Legalization” and Federal Drug Law: A Brief Overview for

Congress, by Joanna R. Lampe (2024).

338 See Pet. for Writ of Mandamus at 13–15, In re Scottsdale Research Inst., No. 19-1120 (D.C. Cir. June 6, 2019).

339 Pub. L. No. 114-89, 129 Stat.703 (2015); 21 U.S.C. § 823(i)(2). “Manufacturing” of controlled substances includes

growing marijuana. See, e.g., Bulk Manufacturer of Controlled Substances Applications: Bulk Manufacturers of

Marihuana, 84 Fed. Reg. 44920 (Aug. 27, 2019).

340 See generally Pet. for Writ of Mandamus, In re Scottsdale Research Inst., No. 19-1120 (D.C. Cir. June 6, 2019).

341 Bulk Manufacturer of Controlled Substances Applications: Bulk Manufacturers of Marihuana, 84 Fed. Reg. 44920,

44921 (Aug. 27, 2019).

342 See Controls to Enhance the Cultivation of Marihuana for Research in the United States, 85 Fed. Reg. 82333 (Dec.

18, 2020).

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consistent with the public interest” and with U.S. treaty obligations.343 The rule further provides

that “[a]ll registered manufacturers who cultivate cannabis shall deliver their total crops of

cannabis” to DEA, and the agency “shall purchase and take physical possession of such crops as

soon as possible” and “have the exclusive right of importing, exporting, wholesale trading, and

maintaining stocks [of cannabis] other than those held by registered manufacturers and

distributors of medicinal cannabis or cannabis preparations.”344 The rule also allows DEA to

delegate some of its responsibilities, such as storage and trading of cannabis, to “appropriately

registered persons.”345 After issuing the final rule, DEA began to issue registrations to additional

manufacturers. As of March 2023, DEA had registered seven marijuana manufacturers.346

On December 2, 2022, President Biden signed into law the Medical Marijuana and Cannabidiol

Research Expansion Act, which aimed to ease requirements for research involving marijuana and

CBD.347 Among other things, the Act created specialized, expedited procedures for DEA approval

of marijuana research and manufacture of marijuana for research purposes.348

Other proposals during the 117th and 118th Congresses sought to facilitate federally approved

clinical research involving marijuana349 or enable veterans to access information about or use

medical marijuana.350 Congress also considered legislation that would have more broadly

facilitated research involving controlled substances. For example, a proposed amendment to an

appropriations bill for FY2022 would have eliminated the appropriations rider restricting the use

of federal funding to promote the legalization of Schedule I controlled substances.351 That

amendment was intended to facilitate research involving not only marijuana but also psilocybin,

MDMA, and other Schedule I drugs that might have legitimate medical uses.352 More recently,

several proposals related to fentanyl analogues also contained provisions that would relax certain

registration requirements related to research on Schedule I controlled substances.353

343 Id. at 82353.

344 Id.

345 Id.

346 Nat’l Ctr. for Complementary & Integrative Health, DEA-Approved Bulk Cannabis Suppliers, HHS,

https://www.nccih.nih.gov/grants/dea-approved-bulk-cannabis-suppliers (last visited Jan. 13, 2025).

347 Pub. L. 117-215, 136 Stat. 2257 (2022).

348 For additional discussion of the Act, see CRS Legal Sidebar LSB10859, Recent Developments in Marijuana Law,

by Joanna R. Lampe (2022).

349 See, e.g., Cannabis Research Act, H.R. 8901, 118th Cong. (2024); Developing and Nationalizing Key Cannabis

Research Act of 2022, H.R. 8540, 117th Cong. (2022); Medical Marijuana Research Act, H.R. 5657, 117th Cong.

(2021).

350 See, e.g., Veterans Equal Access Act, H.R. 2431, 118th Cong. (2023); Veterans Medical Marijuana Safe Harbor

Act, H.R. 2682, S. 1204, 118th Cong. (2023); Fully Informed Veteran Act of 2021, H.R. 3601, 117th Cong. (2021);

Veterans Cannabis Use for Safe Healing Act, H.R. 430, 117th Cong. (2021).

351 H.Amdt. 85 to H.R. 4502, 117th Cong. (2021). The amendment was not adopted.

352 See 166 Cong. Rec. H4074 (daily ed. July 30, 2021) (statement of Rep. Alexandria Ocasio-Cortez) (stating that the

appropriations rider “has, for a very long period of time, prevented and acted as a barricade to Federal research on

certain substances—such as psilocybin, MDMA, and marijuana—in allowing us to research the applications and

potential therapeutic applications of these drugs in the treatment of diseases such as PTSD, addiction, and

depression.”).

353 See SIFT Act of 2023, H.R. 1758, 118th Cong. (2023); TEST Act, S. 1950, 118th Cong. (2023); SAFE Act, H.R.

568, 118th Cong. (2023); HALT Fentanyl Act, S. 1141, 118th Cong. 2023). For additional discussion of regulation of

fentanyl analogues, see infra “Fentanyl Analogues.”

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Opioid Epidemic

Another salient current issue in the realm of controlled substance regulation is the opioid

epidemic.354 Opioids are drugs derived from the opium poppy or emulating the effects of opiumderived drugs.355 Some opioids have legitimate medical uses, primarily related to pain

management, while others have no recognized medical use.356 Both pharmaceutical opioids (such

as fentanyl, oxycodone, codeine, and morphine) and non-pharmaceutical opioids (such as heroin

and some fentanyl analogues) may pose a risk of abuse and dependence and may be dangerous or

even deadly in certain do

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