The Evolution of Marijuana as a Controlled Substance and the Federal-State Policy Gap

The Evolution of Marijuana as a Controlled

Substance and the Federal-State Policy Gap

Updated April 7, 2022

Congressional Research Service

https://crsreports.congress.gov

R44782

SUMMARY

The Evolution of Marijuana as a Controlled

Substance and the Federal-State Policy Gap

R44782

April 7, 2022

Lisa N. Sacco, Coordinator

Marijuana is a psychoactive drug that generally consists of leaves and flowers of the cannabis

Analyst in Illicit Drugs and

Crime Policy

sativa plant. Its history dates back thousands of years, but in the United States it became popular

as a recreational drug in the early 20 th century. Not long after its rise in popularity, the federal

government began to exercise control over marijuana and other substances through its taxing

authority, and it enacted criminal penalties for violations of drug laws. In 1970, the federal

government enacted the Controlled Substances Act (CSA), which imposed a unified legal

framework at the federal level to regulate certain drugs—whether medical or recreational, and legally or illicitly distributed.

The CSA criminalized the manufacture, distribution, dispensation, and possession of marijuana, which included all of

varieties of cannabis at the time (in 2018, the farm bill [P.L. 115-334] amended the CSA to exclude hemp—plant material

that contains no more than 0.3% delta-9-tetrahydrocannabinol [delta-9-THC] on a dry weight basis).

Under the CSA, marijuana and its derivatives are classified as Schedule I controlled substances, which means the cultivation

(or manufacture), possession, and distribution of marijuana are illegal except for the purposes of sanctioned research. While

the CSA definition of marijuana changed in 2018, which resulted in the removal of hemp from the definition of marijuana,

the status of marijuana as a Schedule I substance has remained unchanged for over 50 years. Many states, however, have

established a range of laws and policies allowing for the medical and recreational use of marijuana over the last several

decades. Most of these states have deviated from an across-the-board prohibition of marijuana, and it is now more the rule

than the exception that states have laws and policies allowing for some cultivation, sale, distribution, and possession of

marijuana or low-THC cannabis—many of which are contrary to the CSA. As of April 1, 2022, 37 states, as well as Puerto

Rico, Guam, the U.S. Virgin Islands, and the District of Columbia, allow for the comprehensive medical use of marijuana,

while 11 additional states allow for the medical use of low-THC cannabis. Also, 18 states, the District of Columbia, Guam,

and the Northern Mariana Islands allow for recreational use of marijuana. These developments have spurred a number of

questions regarding potential implications of the federal and state marijuana policy gap for federal law enforcement activities,

for individuals who comply with state marijuana law but violate federal marijuana law, and for the nation’s drug policies as a

whole.

Under the principles of federalism, the federal government may preempt state marijuana laws and enforce the CSA. Thus far,

the federal response to state actions to legalize marijuana has largely been to allow states to implement their own laws on the

drug. The gap between federal marijuana law and federal enforcement policy and the issues it creates continue each year,

although Congress has partly addressed this gap by restricting the Department of Justice’s (DOJ’s) ability to expend funds to

enforce the CSA in states that allow medical marijuana. DOJ has nonetheless reaffirmed that marijuana growth, trafficking,

and possession remain crimes under federal law irrespective of states’ marijuana laws. To date, federal law enforcement has

generally focused its efforts on criminal networks involved in the illicit marijuana trade.

Many observers voice apprehension over possible negative outcomes of marijuana legalization, including, but not limited to,

(1) potential increases in marijuana use, particularly among youth; (2) potential increases in traffic accidents involving

marijuana-impaired drivers; (3) marijuana trafficking from states that have legalized it into neighboring states that have not;

and (4) U.S. compliance with international treaties. Proponents of legalization have pointed to possible positive outcomes

that could result from marijuana legalization, including a new source of tax revenue for states and a decrease in marijuanarelated arrests that would free up resources for other law enforcement needs. Many states have yet to completely assess the

full range of outcomes of their medical or recreational marijuana programs, particularly those that have only recently

legalized the drug.

The marijuana policy gap creates unique consequences for individuals who act in compliance with state law but violate

federal law. As organizations and individuals have pressed forward with the manufacturing, sale, and use of marijuana,

consequences of the gap have arisen—two of the more publicized consequences for individuals are termination of

employment due to marijuana use in states that have legalized medical or recreational marijuana, and a range of implications

for researchers and postsecondary students on college campuses. Other consequences include, but are not limited to, an

inability to obtain or dismissal from certain types of employment, the inability to purchase and possess a firearm,

inadmissibility for federal housing, and ineligibility for certain visas.

Congressional Research Service

The Evolution of Marijuana as a Controlled Substance and the Federal-State Policy Gap

The marijuana policy gap between the federal government and states has widened almost every year for over 25 years as

more states legalize medical and/or recreational marijuana. It has only been a few years since states began to legalize

recreational marijuana, but over 25 years since they began to legalize medical marijuana—no state has reversed its

legalization, medical or recreational, since California first legalized medical marijuana in 1996. In addressing state-level

legalization efforts and considering marijuana’s current placement on Schedule I of the CSA, Congress could take one of

several routes. It could elect to take no action, thereby maintaining the federal government’s current marijuana policy and

allowing the policy gap to expand if additional states legalize medical or recreational marijuana. Alternatively, it may decide

that the CSA must be strictly enforced and not allow states to implement marijuana laws that conflict with the CSA. Or, it

may take smaller steps to address the policy gap, such as continuing to include appropriations provisions that restrict DOJ’s

ability to expend funds to enforce federal law.

Congress could also choose to reevaluate marijuana’s classification as a Schedule I controlled substance. If Congress were to

alter the federal status of marijuana by lowering its schedule or even creating a new schedule, it may devote more resources

to the Food and Drug Administration (FDA) to manage and assess the many medical marijuana products available across the

country. If Congress alters marijuana’s schedule, there are a number of issues that policymakers might address. These

include, but are not limited to, issues surrounding availability of financial services for marijuana businesses, federal tax

treatment, and the role of federal law enforcement in marijuana investigations. If Congress chooses to remove marijuana as a

controlled substance under the CSA and remove criminal provisions, this would at least partly eliminate the policy gap with

states that have authorized medical and recreational marijuana programs.

Whether Congress decides to address the gap with the states or not, federal control of cannabis has evolved from the strict

laws and enforcement policies of the 20th century to allowing most states to implement laws authorizing the production and

distribution of marijuana. Among other things, Congress may halt and reverse this evolution, continue to relinquish federal

criminal control, or alter or eliminate federal criminal control of cannabis entirely.

Congressional Research Service

The Evolution of Marijuana as a Controlled Substance and the Federal-State Policy Gap

Contents

Introduction ..................................................................................................................................... 1

Historical Background of Federal Marijuana Policy ....................................................................... 2

Early 20th Century ..................................................................................................................... 3

Mid-20th Century ....................................................................................................................... 3

Controlled Substances Act .................................................................................................. 4

The Shafer Commission...................................................................................................... 6

Marijuana, Late 20th Century and Beyond ................................................................................ 7

The Federal Status of Marijuana and the Expanding Policy Gap with States ................................. 9

State Cannabis Law and Policy Trends ................................................................................... 10

Medical Marijuana ............................................................................................................. 11

Recreational Marijuana ..................................................................................................... 13

Decriminalization.............................................................................................................. 14

Marijuana as Medicine and Federal Involvement ................................................................... 15

Federal Regulation of Marijuana Research ....................................................................... 16

Exemption of Hemp from the CSA and Implications for Hemp and CBD Oil ....................... 19

Change to CSA Definition of Marijuana........................................................................... 20

Marijuana’s Status Moving Forward....................................................................................... 21

Federal Response to State Divergence .......................................................................................... 21

Federalism: Federal Preemption and the Anti-Commandeering Doctrine .............................. 22

Enforcement Focused on Traffickers ...................................................................................... 22

Department of Justice Guidance Memos for U.S. Attorneys ............................................ 23

Monitoring Enforcement Priorities ................................................................................... 26

Limiting Federal Enforcement in States: Directives through Federal Appropriations ............ 26

Federal Financial Laws and Financial Services for Marijuana Businesses ............................. 29

Bank Secrecy Act and Federal Anti-Money Laundering Laws ......................................... 29

FinCEN Guidance to Financial Institutions ...................................................................... 33

Select Outcomes of State Marijuana Legalization ........................................................................ 34

Marijuana Use in the United States ......................................................................................... 35

Marijuana Use in Washington and Colorado .................................................................... 38

Marijuana-Related Traffic Incidents ....................................................................................... 38

Marijuana Arrests .................................................................................................................... 40

Marijuana Trafficking ............................................................................................................. 41

Transnational Trafficking .................................................................................................. 41

Trafficking from States That Have Legalized into Other States ....................................... 42

The Changing Domestic Black Market............................................................................. 43

Legalization Impact on Criminal Proceeds ....................................................................... 44

Tax Revenue ............................................................................................................................ 46

Employment and Educational Consequences of the Marijuana Policy Gap for Individuals ......... 47

Employment and Legal Marijuana Use ................................................................................... 47

Issues for Students at Postsecondary Institutions .................................................................... 49

Federally Required Institutional Drug Abuse Prevention Policies ................................... 49

Student Eligibility for Federal Student Aid....................................................................... 50

International Policy Context and Response ................................................................................... 51

Select Issues For Congress—The Path Forward ........................................................................... 53

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The Evolution of Marijuana as a Controlled Substance and the Federal-State Policy Gap

Consideration of Marijuana as a Schedule I Drug: Expand, Minimize, or Eliminate

the Policy Gap ...................................................................................................................... 53

Take No Action Regarding the Gap .................................................................................. 53

Bolster the Federal Position or Expand the Gap ............................................................... 53

Minimize the Gap ............................................................................................................. 54

Eliminate the Gap ............................................................................................................. 56

Provision of Financial Services to the Marijuana Industry ..................................................... 56

Federal Tax Treatment ............................................................................................................. 57

Oversight of Federal Law Enforcement in States that have Legalized Marijuana .................. 59

Review of Agency Missions ............................................................................................. 59

Cooperation with State and Local Law Enforcement ....................................................... 59

Evaluating Federal Enforcement Priorities and Monitoring the Effects of State

Legalization of Marijuana .............................................................................................. 60

Medical Marijuana .................................................................................................................. 61

State Medical Marijuana Laws and Federal Law Enforcement ........................................ 61

State Medical Marijuana Laws and the Department of Veterans Affairs .......................... 62

Conclusion .............................................................................................................................. 62

Figures

Figure 1. Public Opinion on Legalization of Marijuana, 1969-2021 .............................................. 9

Figure 2. State Cannabis Laws ....................................................................................................... 11

Figure 3. Estimates of Current Marijuana Use in Colorado, Washington, and the United

States Overall, 2008-2020 .......................................................................................................... 37

Appendixes

Appendix A. Key Terms Used in the Report ................................................................................. 64

Appendix B. Approved Cannabis-Related Drugs and Research ................................................... 66

Appendix C. Research on Effects of Cannabis Use ...................................................................... 71

Appendix D. Federal Regulation of Hemp and CBD .................................................................... 75

Appendix E. Federalism: Federal Preemption and the Anti-Commandeering Doctrine ............... 81

Appendix F. Monitoring Health Concerns Related to Marijuana in Colorado .............................. 93

Contacts

Author Information........................................................................................................................ 95

Subject Matter Experts .................................................................................................................. 95

Congressional Research Service

The Evolution of Marijuana as a Controlled Substance and the Federal-State Policy Gap

Introduction

Marijuana is a psychoactive drug that generally consists of leaves and flowers of the cannabis

sativa plant. Its history dates back thousands of years, but in the United States it became popular

as a recreational drug in the early 20th century.1 The delta-9-tetrahydrocannabinol (THC) content,

which is the primary (but not the only) psychoactive chemical compound (cannabinoid) in

cannabis,2 is dependent on both the variety of the cannabis plant and the part used (see Appendix

A for definitions of key terms used through this report).

Marijuana is the most commonly used illicit drug in the United States.3 The percentage of the

population 12 and older that reported using marijuana in the past month (i.e., current users) has

generally increased over the last decade—from 6.9% in 2010 to 11.8% in 2020.4 For youth (aged

12-17), the rate of past-month marijuana use over the same time period had some small year-toyear percentage changes, but the rate has remained relatively stable, especially when compared to

adult use rates—the rate of past-month marijuana use among youth was 7.4% in 2010 and 6.7%

in 2020.5 During this time span, nearly half of the youth surveyed had a general perception that

marijuana was relatively easy to acquire if desired.6 Marijuana is readily available throughout

most of the United States; in 2020, most Drug Enforcement Administration (DEA) field divisions

reported that marijuana availability was high in their jurisdictions, and since that time more states

have enacted laws authorizing medical and recreational marijuana programs.7

1 David F. Musto, The American Disease: Origins of Narcotic Control, 3rd ed. (New York: Oxford University Press,

1999), p. 219.

2 Other psychoactive compounds, such as delta-8-THC, are also found in cannabis.

3

In 2020, an estimated 32.8 million individuals in the United States aged 12 or older (11.8% of this population) were

current users of marijuana. The Substance Abuse and Mental Health Services Administration (SAMHSA) defines

current use as having used at least once in the past month. See Department of Health and Human Services (HHS),

SAMHSA, Results from the 2020 National Survey on Drug Use and Health: Detailed Tables, October 2021, Tables

1.1A and 1.1B, https://www.samhsa.gov/data/report/2020-nsduh-detailed-tables (hereinafter, “2020 NSDUH Tables”).

4 For each year from 2010 to 2020, the estimated percentage of the population currently using marijuana was 6.9%,

7.0%, 7.3%, 7.5%, 8.4%, 8.3%, 8.9%, 9.6%, 10.1%, 11.5%, and 11.8% respectively. The difference between each

year’s estimate from 2010 to 2018 and the 2019 estimate (11.5%) is statistically significant at the .05 level. SAMHSA

recommends using caution when comparing estimates between 2020 and prior years because of methodological

changes for 2020. Due to these changes, SAMHSA did not conduct significance testing between 2020 and prior years.

For 2002-2020 data, see 2020 NSDUH Tables, Table 7.3B. Of note, some warn of potential bias in drug usage survey

data because of misreporting by respondents. See Beau Kilmer, Jonathan P. Caulkins, and Gregory Midgette et al.,

Before the Grand Opening: Measuring Washington State’s Marijuana Market in the Last Year Before Legalized

Commercial Sales, RAND Drug Policy Research Center, 2013.

5 For some years the difference from one year’s estimate to the next were not statistically significant at the .05 level.

SAMHSA recommends using caution when comparing estimates between 2020 and prior years because of

methodological changes for 2020. Due to these changes, SAMHSA did not conduct significance testing between 2020

and prior years. See 2020 NSDUH Tables, Table 7.6B.

6 In 2010, nearly half (48.6%) of surveyed youth (ages 12-17) indicated that marijuana would be “fairly easy” or “very

easy” to obtain. In 2020, this figure had decreased to 41.0%. See HHS, SAMHSA, Results from the 2010 National

Survey on Drug Use and Health: Summary of National Findings, September 2011, p. 5; and 2020 NSDUH Tables,

Table 3.1B.

7 Just as the CSA does not distinguish between recreational and medical marijuana (it is all prohibited under the CSA),

DEA does not distinguish between medical and recreational marijuana in discussing its availability, nor does it

distinguish between state-authorized and non-state-authorized marijuana availability. U.S. Department of Justice

(DOJ), Drug Enforcement Administration (DEA), 2020 National Drug Threat Assessment, DEA-DCT-DIR-008-21,

March 2021.

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The Evolution of Marijuana as a Controlled Substance and the Federal-State Policy Gap

Under federal law, marijuana and its derivatives8 are classified as Schedule I controlled

substances under the Controlled Substances Act (CSA) unless specifically exempted or listed in

another schedule (see the “Controlled Substances Act” section)—thus, their cultivation,

distribution, or possession, except in the context of approved research studies, is prohibited at the

federal level. In contrast, states have established a range of laws and policies allowing for the

medical and recreational use of marijuana. Most states have deviated from an across-the-board

prohibition of marijuana, and it is now more the rule than the exception that states have laws and

policies allowing for some cultivation, distribution, and possession of marijuana or low-THC

cannabis—many of which are contrary to the CSA. The gap between federal and state laws and

policies on marijuana has expanded each year as states continue to enact laws that allow for the

medical or recreational use of marijuana.

This report provides an historical

Cannabis Terms

background on federal marijuana

The Cannabis sativa plant is often referred to as cannabis, an

umbrella term that includes marijuana and hemp. Marijuana

policy; an overview of state trends

generally refers to the cultivated plant used as a psychotropic

with respect to marijuana

(whether for medicinal or recreational purposes). Hemp,

decriminalization and legalization, for drug

which was removed from the CSA definition of marijuana in 2018,

both medical and recreational uses;

is cultivated for use in the production of a wide range of

and an analysis of the gap between

products, including foods and beverages, personal care products,

dietary supplements, fabrics and textiles, paper, construction

federal and state marijuana law and

materials, and other manufactured and industrial goods. THC and

policy and certain implications and

cannabidiol (CBD) are thought to be the most abundant

consequences of the gap. It reviews

cannabinoids in the Cannabis sativa plant and are among the most

federalism and federal authority to

researched cannabinoids for their potential medical value. While

preempt state marijuana laws and

THC is the primary psychoactive compound found in marijuana,

CBD is a nonpsychoactive compound found in both marijuana and

analyzes relevant issues for federal

hemp.

law enforcement and the

consequences of state marijuana

legalization. The report also outlines a number of related policy questions and options that

Congress may consider, including federal tax treatment of marijuana, financial services for

marijuana businesses, the medical nature of cannabis, oversight of federal law enforcement,

evaluation of marijuana as a Schedule I controlled substance, and some options for addressing the

gap.

Historical Background of Federal Marijuana Policy

To understand the evolution of U.S. marijuana control and the current marijuana policy gap

between the states and the federal government, it is important to examine the history of marijuana

as a controlled substance in the United States.

8 The Agriculture Improvement Act of 2018 (2018 farm bill; P.L. 115-334) removed hemp and hemp derivatives from

the CSA definition of marijuana. Industrial hemp is a variety of the cannabis plant that has low THC content and is

cultivated for use in the production of a wide range of products. Hemp-derived cannabidiol (CBD) is promoted as

treatment for a range of conditions, including epileptic seizures, post-traumatic stress disorder, anxiety, and

inflammation—despite limited scientific evidence to substantiate many of these claims.

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The Evolution of Marijuana as a Controlled Substance and the Federal-State Policy Gap

Early 20th Century

Prior to 1937, growing and using marijuana was legal under federal law.9 During the course of

promoting federal legislation to control marijuana, Henry Anslinger, the first commissioner of the

Federal Bureau of Narcotics (FBN),10 and others submitted testimony to Congress regarding the

immorality and harms of marijuana use, claiming that it incited violent and insane behavior.11

Among other observations, Commissioner Anslinger noted that “the major criminal in the United

States is the drug addict; that of all the offenses committed against the laws of this country, the

narcotic addict is the most frequent offender.”12 States had already begun to ban the possession of

marijuana during this time. The federal government created a de facto ban of marijuana under the

Marihuana Tax Act of 1937 (MTA; P.L. 75-238).13 The MTA imposed a high-cost transfer tax

stamp on marijuana sales, but these stamps were rarely issued by the federal government.14

Early 20th Century Marijuana Control

In the early 20th century, enforcement of drug laws was primarily the responsibility of local police, and the Federal

Bureau of Narcotics (FBN) occasionally assisted.15 Due to reduced appropriations during the Great Depression,

the FBN budget and the number of narcotic agents declined and remained low for years. Publicity and warnings of

the dangers of narcotics, in particular marijuana, were primary methods of drug control for the FBN. 16 In seeking

federal control of marijuana and uniform narcotic laws, Commissioner Anslinger and public officials from some

states made personal appeals to civic groups and legislators and pushed for, and received, editorial support in

newspapers; some newspapers maintained a steady stream of anti-marijuana messaging in the 1930s.17

Mid-20th Century

In the decades that followed the enactment of the MTA, Congress continued to pass drug control

legislation and further criminalized drug use. For example, the Boggs Act (P.L. 82-255), passed in

1951, established mandatory prison sentences for some drug offenses, while the Narcotic Control

Act (P.L. 84-728) in 1956 further increased penalties for drug offenses, including marijuana

offenses. In conjunction with growing support for a medical approach to addressing drug abuse,

9 States regulated marijuana, and some banned it prior to 1937.

10 In 1930, the Federal Bureau of Narcotics (FBN) was established within the U.S. Treasury Department to handle

narcotics enforcement.

11 See statements by H. J. Anslinger, Commissioner of Narcotics, Federal Bureau of Narcotics, U.S. Department of the

Treasury, and Dr. James C. Munch, before the U.S. Congress, House Committee on Ways and Means, Taxation of

Marihuana, 75th Cong., 1st sess., April 27-30, May 4, 1937, HRG-1837-WAM-0002.

12 U.S. Congress, House Committee on Ways and Means, Taxation of Marihuana, 75th Cong., 1st sess., April 27-30,

May 4, 1937, HRG-1837-WAM-0002, p. 7.

13 Congressional testimony indicated that marijuana, while it was a problem in the Southwest United States starting in

the mid-1920s, became a “national menace” in the mid-1930s (1935-1937). See statement by H. J. Anslinger,

Commissioner of Narcotics, Federal Bureau of Narcotics, U.S. Department of the Treasury, before the U.S. Congress,

House Committee on Ways and Means, Taxation of Marihuana, 75th Cong., 1st sess., April 27, 1937. In Leary v. United

States (395 U.S. 6 (1968)), the MTA was overturned by the U.S. Supreme Court as a violation of the Fifth

Amendment’s privilege against compelled self-incrimination.

14 Charles F. Levinthal, Drugs, Society, and Criminal Justice, 3rd ed. (New York, NY: Prentice Hall, 2012), p. 58.

15 David F. Musto, The American Disease: Origins of Narcotic Control, 3rd ed. (New York, NY: Oxford University

Press, 1999), pp. 183-200, p. 228.

16 Ibid., p. 214.

17 Richard J. Bonnie and Charles H. Whitebread II, The Marijuana Conviction: A History of Marijuana Conviction in

the United States (New York, NY: The Lindesmith Center, 1999), pp. 94-95; and Eric Schlosser, “Reefer Madness,”

The Atlantic, August 1994.

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there was a strong emphasis on law enforcement control of drugs, including marijuana—which

was gaining popularity as a recreational drug. Congress shifted the constitutional basis for drug

control from its taxing authority to its power to regulate interstate commerce,18 and in 1968 the

FBN merged with the Bureau of Drug Abuse Control and was transferred from Treasury to the

Department of Justice (DOJ).19 Three years later, President Richard Nixon would declare a war

on drugs.20

Congress and President Nixon enhanced federal control of drugs through the enactment of

comprehensive federal drug laws—including the CSA, enacted as Title II of the Comprehensive

Drug Abuse Prevention and Control Act of 1970 (P.L. 91-513). The CSA placed the control of

marijuana and other plant and chemical substances under federal jurisdiction regardless of state

regulations and laws. In designating marijuana as a Schedule I controlled substance, this

legislation officially prohibited the manufacture, distribution, dispensation, and possession of

marijuana except for purposes of sanctioned research.21

Controlled Substances Act

Marijuana’s listing as a Schedule I controlled substance under the CSA22 indicates that the federal

government has determined that

(A) The drug or other substance has a high potential for abuse.

(B) The drug or other substance has no currently accepted medical use in treatment in the

United States.

(C) There is a lack of accepted safety for use of the drug or other substance under medical

supervision.23

Controlled Substances Act (CSA)

The CSA was enacted as Title II of the Comprehensive Drug Abuse Prevention and Control Act of 1970.24 It

regulates the manufacture, possession, use, importation, and distribution of certain drugs, substances, and

precursor chemicals. The CSA establishes how the federal government (1) regulates and facilitates the lawful

production, possession, and distribution of controlled substances; (2) prevents diversion25 of these substances for

illegitimate purposes; and (3) penalizes unauthorized activities involving controlled substances.

18 As stated in Article I, Section 8, clause 3 of the U.S. Constitution, “Congress shall have the Power ... To regulate

Commerce with foreign Nations, and among the several States, and with the Indian Tribes.” For more information

about the commerce clause, see CRS Report R43023, Congressional Authority to Enact Criminal Law: An

Examination of Selected Recent Cases.

19 David F. Musto, The American Disease: Origins of Narcotic Control, 3rd ed. (New York, NY: Oxford University

Press, 1999), p. 239. The shift in constitutional authority was part of the Drug Abuse Control Amendments of 1965

(P.L. 89-74).

20 For a broader discussion of the federal government’s drug enforcement history, see CRS Report R43749, Drug

Enforcement in the United States: History, Policy, and Trends.

21 21 U.S.C. §812 and §841. Of note, growing a marijuana plant is considered manufacturing marijuana. Marijuana

(spelled as “marihuana”) is defined under 21 U.S.C. §802(16).

22 For more information on the CSA, see the text box, “Controlled Substances Act (CSA),” and U.S. DOJ, DEA, The

Controlled Substances Act, https://www.dea.gov/controlled-substances-act.

23 21 U.S.C. §812(b)(1).

24 P.L. 91-513; 21 U.S.C. §801 et. seq.

25 DEA has explained that the term diversion, used in the context of the CSA, refers to “the redirection of controlled

substances which may have lawful uses into illicit channels.” Controlled Substances Quotas, 83 Federal Register

32784 (July 16, 2018).

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Under the CSA, there are five schedules under which substances may be classified—Schedule I being the most

restrictive. Substances placed onto one of the five schedules are evaluated on



actual or relative potential for abuse;



known scientific evidence of pharmacological effects;



current scientific knowledge of the substance;



history and current pattern of abuse;



scope, duration, and significance of abuse;



risk to public health;



psychic or physiological dependence liability; and



whether the substance is an immediate precursor of an already scheduled substance.

For an overview of the CSA and a discussion of select legal issues that have arisen under the act, see CRS Report

R45948, The Controlled Substances Act (CSA): A Legal Overview for the 117th Congress.

The CSA places various substances in one of five schedules based on characteristics such as their

medical use, potential for abuse, and safety or dependence liability.26 The five schedules are

progressively ordered, with substances regarded as the least dangerous and addictive classified as

Schedule V and those considered the most dangerous and addictive classified as Schedule I.27 As

described in law, Schedule I substances have “a high potential for abuse” with “no currently

accepted medical use in treatment in the United States” and cannot safely be dispensed under a

prescription.28 Schedule I substances may be lawfully used only for bona fide, federal

government-approved research studies.29

The CSA has two overlapping legal schemes. Registration provisions require entities working

with controlled substances, such as those who research marijuana,30 to register with the

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

certain information to regulators.31 Trafficking provisions establish penalties for the production,

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

registration system.32 DEA enforces both registration and trafficking provisions.

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. However, in the event of a knowing

violation, DEA may make an arrest and refer the case to the U.S. Attorney’s Office, which may

bring criminal charges against both individual and corporate registrants. A first criminal violation

of the registration requirements by an individual is punishable by a fine and/or up to a year in

26 21 U.S.C. §812(b).

27 When Congress enacted the CSA in 1970, it established “initial schedules” of controlled substances (21 U.S.C.

§812(c), but specified that the schedules “shall be updated” periodically (21 U.S.C. §812(a)). The current list of

controlled substances within their designated schedules may be found in 21 C.F.R. Sections 1308.11–15.

28 21 U.S.C. §812(b).

29 21 U.S.C. §823(f).

30 Every person or entity who manufactures or distributes any controlled substance, such as drug manufacturing

companies, and every person who dispenses any controlled substance, such as doctors and pharmacists, must register

with DEA.

31 21 U.S.C. §§821-832.

32 21 U.S.C. §§841-865.

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prison.33 For other violations of the CSA, potential penalties vary. Trafficking penalties vary

based on the offense and the type and amount of the controlled substance in question, and certain

sections of the CSA define more specific offenses, such as distributing controlled substances near

schools or to individuals under age 21.34 Unauthorized simple possession of a controlled

substance may prompt a minimum fine of $1,000 and a term of up to a year in federal prison.35

Trafficking of large quantities of Schedule I and Schedule II substances 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.36 Penalties increase for second or subsequent offenses, or if death or serious

bodily injury results from the use of the controlled substance. Simple possession penalties are low

compared to trafficking penalties, and DOJ has infrequently pursued simple possession charges

against offenders compared to trafficking charges.37

The Shafer Commission

As part of the CSA enacted in 1970, the National Commission on Marihuana and Drug Abuse,

also known as the Shafer Commission, was established to study marijuana in the United States.38

Specifically, the commission was charged with performing evaluations and examining issues

including, but not limited to,

(A) the extent of use of marihuana in the United States to include its various sources of

users, number of arrests, number of convictions, amount of marihuana seized, type of user,

nature of use;

(B) an evaluation of the efficacy of existing marihuana laws;

(C) a study of the pharmacology of marihuana and its immediate and long-term effects,

both physiological and psychological;

(D) the relationship of marihuana use to aggressive behavior and crime;

(E) the relationship between marihuana and the use of other drugs; and

(F) the international control of marihuana.39

The Shafer Commission, in concluding its review, produced two reports: (1) Marihuana: A Signal

of Misunderstanding, and (2) Drug Use in America: Problem in Perspective.40

33 21 U.S.C. §842(c)(2)(A).

34 See 21 U.S.C. §859, §860.

35 21 U.S.C. §844(a).

36 21 U.S.C. §841(b)(1)(A). For example, trafficking of 1,000 kilograms or more of a mixture or substance containing a

detectable amount of marijuana, or 1,000 or more marijuana plants regardless of weight, would carry this sentence.

37 In FY2020, 98.4% (16,287) of 16,501 federal drug offenses involved drug trafficking. In FY2020, 19.9% (280) of

1,408 federal marijuana offenses involved marijuana possession and 80.1% (1,128) of federal marijuana offenses

involved marijuana trafficking. See U.S. Sentencing Commission, Quick Facts: Drug Trafficking Offenses, June 2021,

https://www.ussc.gov/; and Interactive Data Analyzer, Sentencing Outcomes for FY2020, https://ida.ussc.gov.

38 The commission was composed of two Members of the Senate, two Members of the House, and nine members

appointed by the President of the United States. President Nixon appointed Raymond Shafer as the chairman.

39 P.L. 91-513, §601(d).

40 National Commission on Marihuana and Drug Abuse, Marihuana: A Signal of Misunderstanding, First Report of the

National Commission on Marihuana and Drug Abuse, Washington, DC, March 1972 (hereinafter, “First Report of the

Shafer Commission”); and National Commission on Marihuana and Drug Abuse, Drug Use in America: Problem in

Perspective, Second Report of the National Commission on Marihuana and Drug Abuse, Washington, DC, March 1973

(hereinafter, “Second Report of the Shafer Commission”).

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In its first report (published in 1972), the Shafer Commission discussed the perception of

marijuana as a major social problem and how it came to be viewed as such.41 It made a number of

recommendations, including the development of a “social control policy seeking to discourage

marihuana use, while concentrating primarily on the prevention of heavy and very heavy use.”42

In this first report, the commission also called the application of criminal law in cases of personal

use of marijuana “constitutionally suspect” and declared that “total prohibition is functionally

inappropriate.”43 Of note, none of the recommendations of this report were implemented, either

administratively or legislatively.

In its second report (published in 1973), the Shafer Commission reviewed the use of all drugs in

the United States, not solely marijuana. It examined the origins of the country’s drug problem,

including the social costs of drug use, and once again made specific recommendations regarding

federal and state drug policy. Among its conclusions regarding marijuana, the commission

indicated that aggressive behavior generally cannot be attributed to its use.44 The commission also

reaffirmed its previous findings and recommendations regarding marijuana and added the

following statement:

The risk potential of marihuana is quite low compared to the potent psychoactive

substances, and even its widespread consumption does not involve social cost now

associated with most of the stimulants and depressants (Jones, 1973; Tinklenberg, 1971).

Nonetheless, the Commission remains persuaded that availability of this drug should not

be institutionalized at this time.45

At the conclusion of the second report, the Shafer Commission recommended that Congress

launch a subsequent commission to reexamine the broad issues surrounding drug use and societal

response.46 While a number of congressionally directed commissions regarding drugs have since

been established,47 no such commission has been directed to comprehensively review the issues

of drug use, abuse, and response in the United States.

Marijuana, Late 20th Century and Beyond

While heroin and cocaine were the primary drugs of concern for federal law enforcement during

the 1970s and 80s (respectively), marijuana was also a target of the substantial investment in

enforcement during the federal government’s “war on drugs.”48 In the 1980s, marijuana arrests

were a large part of federal drug enforcement, and there are some federal crime data available to

41 The commission stated that three factors contributed to the perception of marijuana as a major national problem,

including “[1] the illegal behavior is highly visible to all segments of our society, [2] use of the drug is perceived to

threaten the health and morality not only of the individual but of society itself, and [3] most important, the drug has

evolved in the late sixties and early seventies as a symbol of wider social conflicts and public issues.” First Report of

the Shafer Commission, p. 6.

42 First Report of the Shafer Commission, p. 134.

43 Ibid., pp. 142-143.

44 Second Report of the Shafer Commission, p. 158.

45 Ibid, p. 224. In this statement, the Shafer Commission cites the following studies: R.T. Jones, Mental Illness and

Drugs: Pre-Existing Psychopathology and Response to Psychoactive Drugs, Paper Prepared for the National

Commission on Marihuana and Drug Abuse, 1973; and J.R. Tinklenberg, Marihuana and Crime, Paper Prepared for

the National Commission on Marihuana and Drug Abuse, unpublished, October 1971.

46 Second Report of the Shafer Commission, pp. 410-411.

47 See, for example, the President’s Media Commission on Alcohol and Drug Abuse Prevention and the National

Commission on Drug-Free Schools.

48 President Nixon’s war on drugs involved greater emphasis on a law enforcement response to drug crimes.

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illustrate this. The percentage of federal drug offenders charged with marijuana violations was

24% in 1980, increased to 40% in 1982, and decreased to 26% in 1986. Among federal drug

offenders (12,285) charged with marijuana violations (3,221) in 1986, 70% were charged with

distribution, manufacture, or importation, while the remaining 30% were charged with simple

possession.49 Today, the percentage of federal drug offenders charged with marijuana violations is

much lower—in FY2020, 7% of federal drug offenders were marijuana offenders.50

Over the last several decades, federal law enforcement has generally focused its efforts on

criminal networks rather than individual offenders; its current stance regarding drug (particularly

marijuana) offenders appears consistent with this position.51 DOJ has repeatedly emphasized that

marijuana remains an illegal substance under the CSA, but it chooses to focus its enforcement

efforts on the largest threats (e.g., transnational and domestic criminal organizations that traffic

illicit drugs),52 which generally has not included the state-authorized marijuana industries and

individuals in possession of marijuana.

Since the 1990s, the federal government has shifted its stated drug control policy from one that is

more focused on law enforcement to a comprehensive approach—one that focuses on prevention,

treatment, and enforcement.53 Further, sentencing for federal marijuana offenses has become less

severe over the years. For various reasons, the mean prison sentence for federal marijuana

offenses fell from 50 months in FY1992 to 24 months in FY2020.54

U.S. federal drug control policies—specifically those relating to marijuana—continue to generate

debate among policymakers, law enforcement officials, scholars, and the public. Over the last 25

years since California legalized marijuana for medical purposes, the policy conversation for some

has evolved from how strictly marijuana must be prohibited to how much should be allowed.55

49 DOJ, Bureau of Justice Statistics, Federal Offenses and Offenders: Drug Law Violators, 1980-86, June 1988.

Classifications were based on the most serious offense with which the individual was charged at case filing.

50 U.S. Sentencing Commission, 2020 Annual Report and Sourcebook of Federal Sentencing Statistics, Figure D-1. The

U.S. Sentencing Commission derived information about the type of drug from the primary drug type (i.e., the type that

produces the highest base offense level) in the case, and obtained the data from the presentence report, judgment and

commitment order, or plea agreement. See Appendix A.

51 See DOJ, DEA, FY 2021 Performance Budget Congressional Budget Submission; and U.S. Sentencing Commission,

Quick Facts: Drug Trafficking Offenses.

52 DOJ, DEA, 2020 National Drug Threat Assessment, March 2021.

53 See the annual National Drug Control Strategy and accompanying National Drug Control Budget issued by the

Office of National Drug Control Policy.

54 Some reasons for the decline are discussed in U.S. Sentencing Commission, Mandatory Minimum Penalties for Drug

Offenses in the Federal Criminal Justice System, October 2017, https://www.ussc.gov/sites/default/files/pdf/researchand-publications/research-publications/2017/20171025_Drug-Mand-Min.pdf. One reason is that the number of

offenders convicted of a drug crime carrying a mandatory minimum penalty had decreased by 44.7% from FY2010

through FY2016. See U.S. Sentencing Commission, Interactive Data Analyzer, Sentencing Outcomes for FY2020,

https://ida.ussc.gov; and 1996 Sourcebook of Federal Sentencing Statistics, Figures I and U.

55 For example, see U.S. Congress, House Committee on Interstate and Foreign Commerce, Subcommittee on Public

Health and Welfare, Drug Abuse Control Amendments, 1970, Part 1, 91st Cong., February 3-4, 1970; Robert S.

Weppner and James A. Inciardi, “Decriminalizing Marijuana,” International Journal of Offender Therapy and

Comparative Criminology, vol. 22, no. 2 (June 1, 1978), pp. 115-126; U.S. Congress, House Committee on the

Judiciary, Full Committee Markup on H.R. 3884, the “Marijuana Opportunity Reinvestment and Expungement Act,”

116th Cong., 2nd sess., November 21, 2019; and U.S. Congress, House Committee on the Judiciary, Miscellaneous

Measures, Markup of the H.R. 3617, the Marijuana Opportunity Reinvestment and Expungement Act of 2021 or the

MORE Act of 2021 (among other legislation), 117th Cong., 1st sess., September 29, 2021.

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Evolution of Public Opinion

Changes in state and local marijuana laws over time have corresponded with a general shift in public attitudes

toward the substance (see Figure 1). In 1969, 12% of the surveyed population supported legalizing marijuana; in

2021, that percentage had increased to 68% (+/- 3.0 percentage points).56 Much of the shift in public opinion has

occurred over the last 20 years. In addition, 59% (+/- 2.9 percentage points) of respondents indicated in 2015 that

the federal government should not enforce federal marijuana prohibition laws in states that allow for its use.57

Figure 1. Public Opinion on Legalization of Marijuana, 1969-2021

Source: CRS presentation of data from Gallup News Service, Gallup Poll Social Series: Crime,

http://www.gallup.com.

Notes: The question was “Do you think marijuana should be made legal or not?” Sample sizes and margins of

error vary from year to year. Data from 2021 are based on landline and cellular telephone interviews

conducted October 1-19, 2021, with a random sample of 823 adults aged 18 and older living in the United

States.

The Federal Status of Marijuana and the Expanding

Policy Gap with States

In 1970, the CSA placed the control of marijuana under federal jurisdiction regardless of state

regulations and laws, and while the definition of marijuana has recently been amended to exclude

56 The specific question asked was “Do you think marijuana should be made legal or not?” See Gallup, Support for

Legal Marijuana Holds at Record High of 68%, November 4, 2021 (based on poll data from October 2021). For

purposes of this question, the poll does not distinguish between medical and recreational marijuana, nor does Gallup

explain to respondents what “made legal” means. Of note, in September 2019 the Pew Research Center found similar

(67%) levels of support for marijuana use to be legalized among American adults. For this poll, the specific question

was “Do you think that the use of marijuana should be made legal, or not?”; see Andrew Daniller, Two-thirds of

Americans Support Marijuana Legalization, Pew Research Center, November 14, 2019—data from Pew Research

Center’s online American Trends Panel conducted September 3-15, 2019. In a subsequent poll in 2021, Pew asked a

different marijuana legalization question of survey respondents: “Which comes closer to your view about the use of

marijuana by adults?” 60% of respondents chose “[i]t should be legal for medical AND recreational use”; 30% chose

“[i]t should be legal for medical use ONLY”; and 8% chose “[i]t should NOT be legal.” See Ted Van Green,

Americans Overwhelmingly Say Marijuana Should be Legal for Recreational or Medical Use, Pew Research Center,

April 16, 2021—data from a survey of U.S. adults conducted April 5-11, 2021.

57 Pew Research Center for the People & the Press (Pew), In Debate Over Legalizing Marijuana, Disagreement Over

Drug’s Dangers, April 14, 2015 (based on poll data from March 2015). Of note, Pew has not asked about federal

enforcement of marijuana prohibition laws since the 2015 poll.

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hemp and its derivatives, marijuana’s Schedule I classification has remained unchanged for over

50 years. While the federal government maintains marijuana’s current placement as a Schedule I

controlled substance, states have established a range of laws and policies regarding its medical

and recreational use.

To help illustrate the policy gap between the federal government and states, it is useful to

compare the policies for the cultivation and distribution of marijuana. At the federal level, the

cultivation and distribution of marijuana (regardless of whether it is for medical or recreational

purposes) is considered drug trafficking, and the average prison sentence given to an individual

convicted in federal court of marijuana trafficking was 29 months in FY2020.58 In contrast, in

many states the cultivation and distribution of marijuana is lawful and regulated (see Figure 2),

and marijuana businesses that follow state law and regulation can earn profits from the cultivation

and distribution of marijuana.

While the federal government maintains that marijuana has no medicinal value,59 most states and

territories allow for its use as medicine. While the federal government maintains a prohibition on

marijuana because it is believed to have a high potential for abuse and to be a dangerous

substance, 18 states, the District of Columbia (DC), and two territories allow for its recreational

use. Since the federal government amended its definition of marijuana to exclude hemp, farmers

in states have also forged ahead with hemp production, but they must be careful not to cultivate a

product that has a THC value greater than 0.3% or they would instead be cultivating marijuana.

State Cannabis Law and Policy Trends

Over the past few decades, most states have deviated from an across-the-board prohibition of

cannabis. It is now more the rule than the exception that states have laws and policies allowing

for some manufacturing, sale, distribution, and possession of marijuana—all of which are

contrary to the CSA, except for the purposes of sanctioned research.60 Evolving state-level

positions on marijuana include decriminalization measures as well (for definition of terms such as

decriminalization and legalization, see Appendix A). See Figure 2 for a map of the various

cannabis laws by state.

58 U.S. Sentencing Commission, Quick Facts: Marijuana Trafficking Offenses, June 2021, https://www.ussc.gov/.

59 See Appendix C for a discussion FDA and National Academies evaluations for the health effects of marijuana.

60 With the change to the CSA definition of marijuana in the 2018 farm bill, the states that distribute CBD containing

no more than 0.3% THC may not be in violation of the CSA.

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Figure 2. State Cannabis Laws

April 2022

Source: CRS presentation of data from the National Conference of State Legislatures and CRS review of laws

of the 50 states, territories, and District of Columbia (DC).

Notes: Limited-access medical refers to cannabis with low THC content or CBD oil used for a limited list of

medical conditions. State-approved refers to state laws that either (1) allow for recreational and/or medical

marijuana use and/or (2) decriminalize the possession of marijuana in small amounts. Decriminalization refers to a

state’s action to remove accompanying criminal penalties for possession of marijuana in small amounts; however,

civil penalties remain. Of note, some states allow medical marijuana only for certain specified conditions. Further

detail for the states with state-approved recreational use with no retail include the following: (1) While DC has

approved recreational retail of marijuana, Congress has blocked DC from using funds to regulate and tax

marijuana sales; (2) while Vermont has approved recreational use, it does not have a regulatory system for

production or retail; and (3) the remaining states just recently approved recreational marijuana through a ballot

measure and have not yet set up their retail systems. In 2020, South Dakota (SD) voters approved ballot

measures to legalize recreational and medical marijuana, however, in 2021 a circuit court judge ruled the

recreational measure to be unconstitutional. The SD Supreme Court upheld this ruling in 2021. The SD medical

marijuana program is not yet operational. A 2018 Kansas (KS) law allowed for the sale of CBD products with 0%

concentration of THC, but there is some confusion over the legality of CBD in KS because most CBD products

have trace amounts of THC. Of the U.S. territories, Guam (GU) and the Northern Mariana Islands (MP) have

approved recreational marijuana use and retail. GU, Puerto Rico, MP, and the U.S. Virgin Islands (USVI) have

approved medical marijuana use. USVI has also approved decriminalization of marijuana. American Samoa has not

taken any action to either decriminalize marijuana or approve recreational or medical marijuana.

Medical Marijuana

In 1996, California became the first state to amend its drug laws to allow for the medicinal use of

marijuana. As of April 1, 2022, 37 states, the District of Columbia, Puerto Rico, Guam, and the

U.S. Virgin Islands have comprehensive laws and policies allowing for the medicinal use of

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marijuana.61 Eleven additional states allow for “limited-access medical cannabis,” which refers to

cannabis with low THC content or CBD oil used for a limited list of medical conditions.62 Idaho,

Kansas, Nebraska, and American Samoa do not allow either comprehensive medical marijuana or

low-THC cannabis. While the Northern Mariana Islands allow recreational marijuana, it has not

authorized medical marijuana in any capacity.63

As noted, the CSA does not recognize the distinction states are making between the medical and

recreational use of marijuana. Marijuana’s classification as a Schedule I controlled substance

reflects a finding that marijuana has “no currently accepted medical use in treatment in the United

States.”64 Thus, states allowing its use for medical purposes are still at odds with the federal

position. Federal law enforcement officers and attorneys may investigate, arrest, and prosecute

individuals for medical marijuana-related offenses65; however, annual provisions in DOJ

appropriations restrict DOJ’s ability to expend funds to enforce the CSA in states that allow for

medical use of marijuana (see the “Limiting Federal Enforcement in States: Directives through

Federal Appropriations” section; the appropriations provision does not apply to state laws

allowing recreational use of marijuana). Notwithstanding the appropriations rider, marijuanarelated activity in states that allow for it may still result in serious legal consequences under

federal law. DOJ-issued guidance in 2018 reaffirmed the authority of federal prosecutors to

exercise prosecutorial discretion to target federal marijuana offenses “in accordance with all

applicable laws, regulations, and appropriations.”66 DOJ emphasizes the investigation and

prosecution of growers and dispensers who are violating state law and does not target those that

are in compliance with state law and individual users of medical marijuana.67 (Federal

enforcement priorities are discussed further in the “Federal Response to State Divergence”

section.)

61 In November, 2020, Mississippi voters passed a ballot initiative to allow for medical marijuana, but it was overturned

by the Supreme Court of Mississippi on May 14, 2021. On February 2, 2022, a new comprehensive medical marijuana

law was enacted in Mississippi. See National Conference of State Legislatures, State Medical Marijuana Laws,

February 3, 2022. “Comprehensive” medical programs describe those that allow adults to use a range of marijuana

products (not only low-THC cannabis) to treat specified medical issues. Most states specify conditions for which

medical marijuana may be used as treatment. Prior to enactment of the 2018 farm bill, CBD was considered to be

marijuana under the CSA. See the “Change to CSA Definition of Marijuana” section of this report.

62 As previously mentioned, CBD is a chemical compound in marijuana. Unlike THC, it does not have a psychoactive

component.

63 National Conference of State Legislatures, State Medical Marijuana Laws, February 3, 2022 and CRS review of laws

of the 50 states, territories, and District of Columbia (DC).

64 21 U.S.C. §812(b)(1).

65 Several courts have interpreted the appropriations rider to bar DOJ from expending any appropriated funds to

prosecute activities involving marijuana that are conducted in “strict compliance” with state law. See United States v.

McIntosh, 833 F.3d 1163, 1178 (9th Cir. 2016); Duval v. United States, 372 F. Supp. 3d 544, 555-56 (E.D. Mich.

2019); Sandusky v. Goetz, 2018 WL 6505803 at *4-5 (D. Colo. December 11, 2018); United States v. Jackson, 2019

WL 3239844 at *6-8 (E.D. Pa. June 5, 2019). However, activities that fall outside the scope of state medical marijuana

laws remain subject to prosecution. For example, in United States v. Evans, the Ninth Circuit upheld the prosecution of

medical marijuana growers who smoked some of the marijuana they grew because the defendants failed to show they

were “qualifying patients” who acted in strict compliance with state medical marijuana law.

66 Attorney General Jefferson B. Sessions, Memorandum for All United States Attorneys, U.S. Department of Justice,

Marijuana Enforcement, Washington, DC, January 4, 2018.

67 Communication between CRS and DEA on December 29, 2020. See also discussion in the “Enforcement Focused on

Traffickers” section.

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Recreational Marijuana

Recreational marijuana legalization measures remove all state-imposed penalties for specified

activities involving marijuana. As of April 1, 2022, 18 states, DC, Guam, and the Northern

Mariana Islands allow for the recreational use of marijuana. Until 2012, the recreational use of

marijuana had not been legal in any U.S. state since prior to the passage of the CSA in 1970. In

November 2012, citizens of Colorado and Washington voted to legalize, regulate, and tax

marijuana for recreational use.68 In November 2014, recreational marijuana legalization initiatives

also passed in Alaska, Oregon, and DC. Two years later, in November 2016, recreational

marijuana legalization initiatives passed in Massachusetts, California, Maine, and Nevada. In

2018, Michigan voters approved recreational marijuana use through a ballot initiative, and

Vermont approved recreational marijuana use through the legislative process—the first state to

approve recreational marijuana via legislation as opposed to a ballot initiative. In 2019, Illinois

became the second state to enact legislation approving recreational marijuana use. In 2020, voters

in Arizona, Montana, New Jersey, and South Dakota approved measures to allow recreational

marijuana; however, in February 2021 a circuit judge ruled the South Dakota recreational

marijuana measure to be unconstitutional.69 In 2021, New York, Virginia, and Connecticut

approved recreational marijuana through the legislative process.

These recreational marijuana initiatives legalized the possession of specific quantities of

marijuana by individuals aged 21 and over, and (with the exception of DC and Vermont) set up

state-administered regulatory schemes for the sale of marijuana70; however, there are variations

among the initiatives. For example, Alaska, Arizona, California, Colorado, Connecticut,

Massachusetts, Maine, Michigan, Montana, Nevada, New Mexico, Oregon, Vermont, Virginia,

and DC allow individuals to grow their own marijuana plants for recreational use,71 while Illinois,

New Jersey, and Washington do not. Currently, New York allows hemp farmers72 to grow

marijuana for recreational purposes, while all adults age 21 and older will be allowed to grow

their own plants 18 months after retail sales begin in the state.73 Recreational marijuana

legalization initiatives also specify that many activities involving marijuana remain crimes. For

example, in most states that have legalized recreational marijuana, it remains illegal to consume

marijuana in a public place.

68 For more detail regarding both Washington Initiative 502 and Colorado Amendment 64, see CRS Report R43034,

State Legalization of Recreational Marijuana: Selected Legal Issues.

69 On November 24, 2021, the South Dakota Supreme Court upheld this decision. See Teo Armus, “South Dakota

voters said yes to legalizing marijuana. But a judge ruled it’s unconstitutional,” The Washington Post, February 9,

2021; and Jonathan Ellis and Joe Sneve, “South Dakota Supreme Court strikes down recreational marijuana

amendment,” Argus Leader, November 24, 2021.

70 Regulatory schemes include restrictions and requirements for licensing the production, processing, and retail of

marijuana, and procedures for the issuance of licenses.

71 South Dakota’s Constitutional Amendment A would have allowed individuals to grow their own marijuana plants for

recreational use, but a circuit court judge ruled the amendment to be unconstitutional. When New York enacts

regulations for home grown marijuana plants, individuals in the state will be allowed to grow plants as well.

Connecticut will allow for recreational home cultivation beginning July 1, 2023. See Teo Armus, “South Dakota voters

said yes to legalizing marijuana. But a judge ruled it’s unconstitutional,” The Washington Post, February 9, 2021; Don

Cazentre, NewYorkUpstate.com, “Legal marijuana in NY: What you need to know about possession, growing, business

opportunities,” April 6, 2021; and State of Connecticut, Governor Ned Lamont, Governor Lamont Signs Bill Legalizing

and Safely Regulating Adult-Use Cannabis, press releases, June 22, 2021.

72 In order to meet state licensing requirements, farmers must have been growing hemp for at least two of the previous

four years. See NY S.B. 8084.

73 See Marijuana regulation and taxation act, 2021, NY S.B. 854.

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Decriminalization

Marijuana decriminalization differs markedly from legalization. A state decriminalizes conduct

by lowering (e.g., making it a low-level misdemeanor with no possibility of jail time) or

removing the accompanying criminal penalties; however, civil penalties may remain. If, for

instance, a state decriminalizes the possession of marijuana in small amounts,74 possession of it

may still violate state law, but possession of quantities within the specified small amount may be

considered a civil offense and subject to a civil penalty (e.g., a civil fine), not criminal

prosecution. By decriminalizing possession of marijuana in small amounts, states are not

legalizing its possession. Legalizing possession or other conduct involving marijuana would make

that activity legal, or allowable under law, but that is not what decriminalization does. It may

remain a low-level misdemeanor, or it may become a civil or local infraction.

Decriminalization initiatives by the states do not appear to be at odds with the CSA because both

maintain that possessing marijuana is in violation of the law. For example, individuals in

possession of one ounce or less of marijuana in Nebraska are in violation of both the CSA and

Nebraska state law. The difference lies in the associated penalties for these federal and state

violations. Under the CSA, a person convicted of simple possession (first offense) of marijuana

may be punished with up to one year imprisonment and/or fined not more than $1,000.75 Under

Nebraska state law, a person in possession (first offense) of an ounce or less of marijuana is

subject to a civil penalty of not more than $300.76

Decriminalization in Cities

Just as there are disparities between state and federal marijuana laws and policies, some cities’

decriminalization initiatives run contrary to the laws and policies of their states. Several cities

have by law or policy decriminalized marijuana possession independent of what has occurred at

the state level. For example, in November 2014, prior to New York State’s decriminalization of

marijuana possession in 2019, former New York City (NYC) Mayor de Blasio and former-NYC

Police Commissioner Bratton announced a change in marijuana enforcement policy; individuals

found to be in possession of 25 grams or less of marijuana77 may have been eligible to receive a

summons instead of being arrested.78

In Pennsylvania, the state government has not decriminalized marijuana possession,79 but

Pittsburgh, Philadelphia, State College, Harrisburg and other cities in Pennsylvania have all

decriminalized possession in some form. For example, in 2016 Harrisburg’s city council

74 Typically one ounce or less, but the amount varies from state to state.

75

21 U.S.C. §844.

76 Also, the judge may order the offender to attend a drug use and abuse education course. See Section 28-416 of the

Nebraska Revised Statutes.

77 Under NY Pen. Law Section 221.10 in 2014, a person was guilty of criminal possession of marijuana in the fifth

degree when he knowingly and unlawfully possessed “1. marihuana in a public place ... and such marihuana is burning

or open to public view; or 2. one or more preparations, compounds, mixtures or substances containing marihuana and...

are of an aggregate weight of more than twenty-five grams.”

78 City of New York, Transcript: Mayor de Blasio, Police Commissioner Bratton Announce Change in Marijuana

Policy, November 10, 2014.

79 Under Pennsylvania state law, the possession of 30 grams or less of marijuana is a misdemeanor offense punishable

by 30 days in jail and/or a $500 fine.

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unanimously voted to make possession of 30 grams or less of marijuana punishable by a $75 fine

and public use punishable by a $150 fine.80

Marijuana as Medicine and Federal Involvement

During the past 25 years, there have been significant policy shifts at the state level to allow

certain patients to obtain marijuana for medicinal purposes. However, the federal government

does not recognize marijuana as having any currently accepted medical use, and it continues to be

listed on Schedule I under the CSA. Under federal law, a drug must be approved by the Food and

Drug Administration (FDA) before it may be marketed in the United States. To date, FDA has not

approved a marketing application for marijuana for the treatment of any condition. However,

FDA has approved one marijuana-derived drug and three marijuana-related drugs that are

available by prescription. Epidiolex, which contains CBD as its active ingredient, is approved for

the treatment of seizures associated with two rare and severe forms of epilepsy. It is the first (and

only) FDA-approved drug containing a purified drug substance derived from marijuana.81

Following its approval, DEA issued an order placing FDA-approved drugs that contain cannabisderived CBD with no more than 0.1% THC on Schedule V of the CSA, and in April 2020 DEA

notified GW Pharmaceuticals that Epidiolex is no longer subject to the CSA.82 FDA has also

approved two drugs containing synthetic THC (i.e., Marinol [and its generic versions] and

Syndros) and one drug containing a synthetic substance that is structurally similar to THC but not

present in marijuana (i.e., Cesamet). These products are used to treat nausea and vomiting caused

by chemotherapy as well as loss of appetite for individuals with human immunodeficiency virus

(HIV). Additional drugs containing marijuana-derived THC and CBD are reportedly being

developed (see Appendix B for further discussion).83

Although FDA has approved only one marijuana-derived drug and three marijuana-related drugs

for specific purposes, some states allow for dispensing of marijuana for a wide range of medical

conditions. To date, there is insufficient scientific evidence to support claims of the effectiveness

of marijuana for treating many of these conditions. In 2017, the National Academies of Sciences,

Engineering, and Medicine (NASEM) issued a report evaluating the use of cannabis and its

constituent substances for various diseases and conditions (for more information about the report,

see Appendix C). In general, the NASEM found conclusive or substantial evidence that cannabis

or cannabinoids (but not necessarily marijuana or marijuana-derived cannabinoids) are an

effective treatment for chronic pain, chemotherapy-induced nausea and vomiting, and selfreported symptoms of spasticity (i.e., intermittent or constant involuntary muscle movement)

among patients with multiple sclerosis. However, for the remaining conditions examined, the

80 Christine Vendel, “It’s official: Harrisburg council reduces penalties for pot possession,” Penn Live, July 5, 2016;

and City of Harrisburg, City Council.

81 The U.S. Food and Drug Administration (FDA), “FDA approves first drug comprised of an active ingredient derived

from marijuana to treat rare, severe forms of epilepsy,” June 25, 2018, https://www.fda.gov/newsevents/newsroom/

pressannouncements/ucm611046.htm.

82 DOJ, DEA, “Schedules of Controlled Substances: Placement in Schedule V of Certain FDA-Approved Drugs

Containing Cannabidiol; Corresponding Change to Permit Requirements,” 83 Federal Register 48950, September 28,

2018; GW Pharmaceuticals, GW Pharmaceuticals plc and Its U.S. Subsidiary Greenwich Biosciences, Inc. Announce

That EPIDIOLEX® (cannabidiol) Oral Solution Has Been Descheduled And Is No Longer A Controlled Substance,

press release, April 6, 2020, https://ir.gwpharm.com/news-releases/news-release-details/gw-pharmaceuticals-plc-andits-us-subsidiary-greenwich-1.

83 National Institutes of Health (NIH), National Library of Medicine, Clinicaltrials.gov, accessed January 13, 2022,

https://clinicaltrials.gov/ct2/results?cond=&term=Cannabidiol&cntry=&state=&city=&dist=.

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NASEM found insufficient or no evidence of potential therapeutic effects of cannabis or

cannabinoids.

Randomized controlled trials (RCTs) are considered the gold standard of clinical and

epidemiologic research to determine if a proposed treatment (e.g., marijuana) is more effective

than an existing treatment or no treatment (i.e., placebo). As of January 2022, a database

maintained by the National Library of Medicine (NLM) at the National Institutes of Health (NIH)

lists numerous domestic and international RCTs involving cannabinoids—including THC and

CBD—derived from marijuana as treatment for a variety of conditions, including Amyotrophic

Lateral Sclerosis (ALS), pain, and schizophrenia.84 However, much of this research is in its

nascent stages; therefore, conclusive evidence on the use of marijuana to treat various health

conditions will likely not be available for some time. There are also still many unknowns

regarding how marijuana would be used as a medical treatment if approved, including the

individual and combined clinical benefits of THC, CBD, and other cannabinoids; proper dosage;

and effects of different routes of administration, among others.85 In addition, the short- and longterm health effects of marijuana use are also largely unknown, in part due to the challenges of

researching marijuana in the United States.86

Federal Regulation of Marijuana Research

Conducting research with marijuana involves several federal agencies: DEA, FDA, and the

National Institute on Drug Abuse (NIDA), which is housed within NIH. Before conducting

research with marijuana, an investigator must obtain a DEA registration,87 an FDA review of an

investigational new drug application (IND) or research protocol, and marijuana from NIDA or

another DEA-registered source.88 The U.S. Department of Health and Human Services (HHS) has

issued guidance to aid researchers in conducting medical research on marijuana in compliance

with DEA, FDA, and NIDA requirements if the researcher chooses to obtain their marijuana

through NIDA’s Drug Supply Program (DSP).89 For all controlled substances, researchers must

obtain a registration issued by the Attorney General (DEA, by delegation of authority),90 in

84 See NIH’s database at https://clinicaltrials.gov/ct2/home (accessed January 13, 2022).

85 National Academies of Sciences, Engineering, and Medicine (NASEM), The Health Effects of Cannabis and

Cannabinoids: The Current State of Evidence and Recommendations for Research, Washington, DC, 2017, doi:

10.17226/24625, p. 396.

86 The Schedule I status of marijuana has reportedly created difficulty for researchers who seek to study marijuana but

are potentially unable to meet the strict requirements of the CSA or seek a different strain, potency, or quality of

marijuana for their research than what is lawfully available. See Heike Newman, “Cannabis Clinical Investigations in

Colorado 2019,” Food and Drug Law Institute, July/August 2019; L. Sanders, “The CBD Boom is Way Ahead of the

Science,” Science News, March 27, 2019; and NASEM, The Health Effects of Cannabis and Cannabinoids: The

Current State of Evidence and Recommendations for Research, Washington, DC, 2017, doi: 10.17226/24625, p. 396.

87 A separate, additional registration is needed for Schedule I substances.

88 As of April 1, 2022, there are five federally registered manufacturers of marijuana.

89 DEA has registered additional marijuana growers outside of NIDA’s DSP, and researchers will have options beyond

what is available through the DSP. See DOJ, DEA, “Controls To Enhance the Cultivation of Marihuana for Research in

the United States,” 85 Federal Register 82333-82355, December 18, 2020; and NIH, “Announcement for the

Department of Health and Human Services’ Guidance on Procedures for the Provision of Marijuana for Medical

Research,” May 1999, https://grants.nih.gov/grants/guide/notice-files/not99-091.html. For regulatory requirements

under the CSA, see CRS Report R45948, The Controlled Substances Act (CSA): A Legal Overview for the 117th

Congress.

90 As authorized under 21 U.S.C. Section 871, the Attorney General may delegate any of his/her control and

enforcement functions under the CSA to any DOJ officer or employee—many of these functions are performed by

DEA.

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accordance with relevant federal law and regulations.91 Among other requirements, DEA and

FDA regulations require registrants to comply with strict storage requirements for controlled

substances.92 CSA requirements are most stringent for Schedule I substances (these requirements

are discussed further in Appendix B). In addition to federal requirements, some states require

researchers to comply with state-specific medical or government requirements to conduct clinical

trials or other activities involving Schedule I substances.93

To obtain a DEA registration for purposes of conducting research with a Schedule I controlled

substance (e.g., marijuana), the applicant must submit to DEA a protocol containing specified

information, including a description of the planned research and information about the quantity of

the substance to be used for it.94 DEA must process the registration application and research

protocol and forward a copy of each to the HHS Secretary (FDA, by delegation of authority)

within seven days of receipt. If the Schedule I controlled substance is intended to be studied in

human clinical trials, the researcher must obtain a pre-IND number from FDA, submit the IND to

FDA, and certify to DEA that the IND has been submitted to FDA.95 An IND must include

information about the proposed clinical study design, completed animal test data, and the lead

investigator’s qualifications, among other things.96 For INDs concerning Schedule I controlled

substances, FDA is required, within 30 days of receipt, to review and comment on the scientific

merit of the studies and qualifications of the investigators conducting the research and to report

this information to DEA.97 For a research protocol, FDA must provide this information to DEA

within 21 days of receipt of the protocol.98

If FDA determines that the applicant is qualified and competent and the research protocol is

meritorious, it notifies DEA of such determination. If FDA determines that the protocol is not

meritorious and/or the applicant is not qualified or competent, it must notify DEA of this

determination and provide the reasons for it.99 DEA is required to issue a certificate of registration

within 10 days of receiving FDA’s notice, unless DEA determines that the certificate should be

denied.100 DEA makes the final determination on approving research using Schedule I substances

and drugs.101

91 See 21 U.S.C. §822. This requirement is also described under 21 C.F.R. Section 1301.11(a): “Every person who

manufactures, distributes, dispenses, imports, or exports any controlled substance or who proposes to engage in the

manufacture, distribution, dispensing, importation or exportation of any controlled substance shall obtain a registration

unless exempted by law or pursuant to §§1301.22 through 1301.26.”

92 For the purposes of ensuring the secure storage and distribution of all controlled substances, all applicants and

registrants must generally “provide effective controls and procedures to guard against theft and diversion of controlled

substances.” See 21 C.F.R. §1301.71. FDA’s investigational new drug regulations provide that if the investigational

drug is a controlled substance, the investigator must take adequate precautions, including proper storage of the drug “to

prevent theft or diversion of the substance into illegal channels of distribution.” See 21 C.F.R. §312.69.

93 NASEM, The Health Effects of Cannabis and Cannabinoids: The Current State of Evidence and Recommendations

for Research, Washington, DC, 2017, doi: 10.17226/24625, p. 380.

94 21 C.F.R. §1301.18.

95 NIH, “Announcement for the Department of Health and Human Services’ Guidance on Procedures for the Provision

of Marijuana for Medical Research,” May 1999, https://grants.nih.gov/grants/guide/notice-files/not99-091.html.

96 21 C.F.R. Part 312.

97 21 C.F.R. §1301.32(a).

98 Ibid.

99 21 C.F.R. §1301.32(c).

100 21 C.F.R. §1301.32(b).

101 21 C.F.R. §1301.32; and FDA Manual of Policies and Procedures MAPP 4200.1, “Consulting the Controlled

Substance Staff on INDs and Protocols That Use Schedule I Controlled Substances and Drugs,” https://www.fda.gov/

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Researchers should soon be able to acquire marijuana for research through DEA and its registered

marijuana growers. Currently, researchers may only gain access to marijuana through NIDA. If

researchers continue to access marijuana through NIDA, they must comply with NIH

requirements. NIDA supplies researchers with marijuana from the National Center for Natural

Products Research at the University of Mississippi, which has a contract with NIDA. This was the

only official source in the United States through which researchers could obtain marijuana for

research purposes for over 50 years.102 Researchers who seek to use this source need to make an

inquiry to NIDA to determine availability and associated costs. If NIDA determines that

marijuana is available for the researcher’s study, it will provide the researcher with a letter of

authorization (LOA) to reference NIDA’s marijuana Drug Master File (DMF) on file with

FDA.103 As of April 1, 2022, DEA has five registered manufacturers of marijuana. According to

DEA, researchers will be able to obtain marijuana from these growers with minimal DEA

involvement.104

Some researchers have argued that the federal regulations that guide marijuana research

unnecessarily impede its advancement.105 DOJ and HHS have taken some steps to make

marijuana research easier, including the following:



In June 2015, HHS eliminated one step in obtaining research-grade marijuana for

research that is not funded by NIH. HHS eliminated the Public Health Service

review of non-federally funded research protocols involving marijuana and the

utilization of the existing FDA IND process for drug development.106



In December 2015, DEA announced a waiver to make it easier for researchers

conducting clinical trials with CBD to modify their research protocols and obtain

more CBD than was initially approved.107

In August 2016, DEA announced a new policy intended to increase the number of

approved sources of research-grade marijuana.108



media/71646/download.

102 NIDA, “NIDA’s Role in Providing Marijuana for Research,” https://www.drugabuse.gov/drugs-abuse/marijuana/

nidas-role-in-providing-marijuana-research.

103 A DMF is a submission to FDA “that may be used to provide confidential detailed information about facilities,

processes, or articles used in the manufacturing, processing, packaging, and storing of one or more human drugs.” See

FDA, “Drug Master Files (DMFs),” https://www.fda.gov/drugs/forms-submission-requirements/drug-master-filesdmfs.

104 See DOJ, DEA, “Controls To Enhance the Cultivation of Marihuana for Research in the United States,” 85 Federal

Register 82340, December 18, 2020.

105 See NASEM, The Health Effects of Cannabis and Cannabinoids: The Current State of Evidence and

Recommendations for Research, Washington, DC, 2017, doi: 10.17226/24625, p. 382; and Pet. for Writ of Mandamus

at 13, In re Scottsdale Research Inst., No. 19-1120 (D.C. Cir. June 6, 2019).

106 HHS, “Announcement of Revision to the Department of Health and Human Services Guidance on Procedures for

the Provision of Marijuana for Medical Research as Published on May 21, 1999,” 80 Federal Register 35960-35961,

June 23, 2015.

107 DOJ, DEA, “DEA Eases Requirements for FDA-Approved Clinical Trials on Cannabidiol,” press release, December

23, 2015.

108 DOJ, DEA, “Applications to Become Registered under the Controlled Substances Act to Manufacture Marijuana to

Supply Researchers in the U.S.,” 81 Federal Register 53846-53848, August 12, 2016.

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

In August 2019, former Attorney General Barr announced that DEA is “moving

forward with its review of applications for those who seek to grow marijuana

legally to support research.”109



In December 2020, DEA published a final rule that, among other things, requires

all registered manufacturers who cultivate marijuana (for research purposes only)

“to deliver”110 their total crops to DEA with limited exception; however, the

crops may remain at the manufacturers’ registered locations. DEA is to purchase

and take possession of such crops (not later than four months after harvest ends)

by designating a secure storage mechanism at the registered location and

controlling access to the marijuana.111

Some have contended that marijuana provided to researchers is “both qualitatively and

quantitatively inadequate.”112 DEA’s addition of new manufacturers of marijuana may lead to

better quality and a sufficient quantity of marijuana for research purposes. As of April 1, 2022,

DEA has five registered marijuana growers listed on their website.113 (For further discussion of

the marijuana supply policy issue, see Appendix B.)

Exemption of Hemp from the CSA and Implications for Hemp and

CBD Oil

From 1970 until 2018, the federal government’s definition of marijuana included hemp and its

derivatives, and widespread hemp production was generally prohibited. In 2018, Congress

amended the definition to reflect the differences in the chemical and psychoactive properties

between hemp and marijuana.

109

DOJ, DEA, DEA announces steps necessary to improve access to marijuana research, press release, August 25,

2019, https://www.dea.gov/press-releases.

110 The marijuana is not technically delivered to DEA but rather DEA travels to the manufacturer and accepts delivery

at the manufacturer’s registered location, where DEA will maintain possession or designate a different location if

adequate storage does not exist at the manufacturer’s registered location.

111 DOJ, DEA, “Controls To Enhance the Cultivation of Marihuana for Research in the United States,” 85 Federal

Register 82333-82355, December 18, 2020.

112 Marc Kaufman, “Federal Marijuana Monopoly Challenged,” Washington Post, December 12, 2005; and DOJ, DEA,

“Lyle E. Craker; Denial of Application,” 74 Federal Register 2101, January 14, 2009.

113 DOJ, DEA, Diversion Control Division, Marihuana Growers Information, https://www.deadiversion.usdoj.gov/

drugreg/marihuana.htm.

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Distinguishing Between Hemp and Marijuana Plants for Law

Enforcement Purposes

It is difficult for law enforcement to distinguish between hemp and marijuana plants—both are cannabis plants, but

hemp is defined in statute as containing no more than 0.3% delta-9-THC. These plants look, smell, and feel the

same. Drug-sniffing dogs are unable to distinguish between them.114

While a binary roadside test is available to U.S. law enforcement115 to help determine the nature of a product (i.e.,

whether it is hemp or marijuana), a roadside test that gives the exact percentage of THC is not yet available. 116

These precision tests must currently be conducted in a laboratory.

Change to CSA Definition of Marijuana

The 2018 farm bill (P.L. 115-334) amended the CSA to exclude hemp—plant material that

contains no more than 0.3% delta-9 THC on a dry weight basis117—from the statutory definition

of marijuana.118 This provision allows for the cultivation of hemp and hemp-derived products at

or below the 0.3% delta-9 THC threshold,119 as defined in statute, from being regulated as a

Schedule I controlled substance. A DEA registration is no longer required to cultivate or research

hemp and hemp-derived products; however, hemp remains subject to U.S. Department of

Agriculture (USDA) regulation. Further, it remains subject to DEA scrutiny due to the nature of

cannabis and methods of production.120 Changes enacted in the 2018 farm bill now allow for the

cultivation, processing, marketing, and sale of hemp and hemp-derived products that meet the

statutory definition of hemp—if it is produced by an authorized grower in accordance with the

2018 farm bill, associated federal USDA regulations, and applicable state regulations.121 (See

Appendix D for further information regarding federal regulation of hemp production.)

114 Debra Cassens Weiss, “New Hemp Laws Leave Police and Prosecutors Dazed and Confused,” ABA Journal, August

9, 2019.

115 The test turns one color when detecting products with a higher concentration of THC and another color if the

product has low THC. Jodie Fleischer, Katie Leslie, and Steve Jones et al., “New Police Drug Test Aims to Tell Pot

From CBD,” NBC Washington, July 18, 2019; and CRS correspondence with DEA, July 9, 2019.

116 New field tests with more precision are in development. See, for example, Olga Kuchment, “Is it hemp or

marijuana? Scanning technology may provide an instant answer,” AgriLife Today, February 10, 2020.

117 Dry weight basis means the weight of the material after it has been dried at high temperature (generally until

reaching a constant mass).

118 For the CSA definition of marijuana, see 21 U.S.C. §802(16).

119 While Epidiolex—a marijuana-derived drug—contains less than 0.3% delta-9 THC, it was approved and placed in

Schedule V prior to the enactment of the 2018 farm bill (i.e., prior to the change in the statutory definition of

marijuana). As such, despite meeting the current statutory definition of hemp in 7 U.S.C. Section 1639o, it remains in

Schedule V. 83 Federal Register 48950, September 28, 2018.

120 Remaining concerns for farmers and manufacturers of hemp and CBD products are accidental growth of marijuana

plants instead of hemp plants and the THC level changes (sometimes over the 0.3% threshold) during the

manufacturing process. In August 2020, DEA issued an interim final rule to formally provide in their regulations the

scope of DEA regulatory controls over marijuana, THC, and other marijuana-related constituents and acknowledge the

change to the CSA definition of marijuana to exclude hemp and its constituents. See DOJ, DEA, “Implementation of

the Agriculture Improvement Act of 2018,” 85 Federal Register 51639-51645, August 21, 2020.

121 Regulatory plans involving hemp under the oversight of states and tribes will need to include the following

requirements: maintenance of relevant production information; THC testing; procedures for disposal of plants (and

products from those plants) that exceed hemp THC levels; procedures to comply with USDA’s enforcement provisions;

procedures for conducting random, annual inspections of hemp producers; procedures for submitting hemp production

information to USDA; and certification by state and tribal regulators that they have adequate resources and personnel to

implement required procedures.

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Marijuana’s Status Moving Forward

Over the years, several entities have submitted petitions to DEA to reschedule marijuana.122 In

August 2016, after a five-year evaluation process done in conjunction with FDA, DEA rejected

two petitions, one submitted by two state governors and a second submitted by a New Mexico

health provider, to move marijuana to a less-restrictive schedule under the CSA.123 Consistent

with past practice,124 the rejections were based on a conclusion by both FDA and DEA that

marijuana continues to meet the criteria for inclusion on Schedule I—namely that it has a high

potential for abuse, has no currently accepted medical use, and lacks an accepted level of safety

for use, even under medical supervision.125

Congress (through legislation and hearings) has also demonstrated interest in altering the

schedule status of marijuana. In recent years, Members of Congress have introduced various bills

that would change the Schedule I status of marijuana. In the 116th and 117th Congress, for

instance, the House passed the Marijuana Opportunity Reinvestment and Expungement Act of

2019 (MORE Act; H.R. 3884) and the MORE Act of 2021 (H.R. 3617), respectively. The MORE

Act (both H.R. 3884 from the 116th Congress and H.R. 3617 from the 117th Congress) would

remove marijuana from CSA control entirely, among other things. The Senate did not vote on the

MORE Act in the 116th Congress, and as of April 1, 2022, it has not taken up H.R. 3617. Several

other bills that would deschedule or alter the Schedule I status of marijuana have been introduced

in the 117th Congress.

Federal Response to State Divergence

Although state laws do not affect the status of marijuana under federal law or the ability of

federal law enforcement to enforce it, state legalization initiatives have spurred a number of

questions regarding potential implications for federal laws and policies, including federal drug

regulation and enforcement, and banking for marijuana businesses. Thus far, the federal response

to states’ decriminalizing or legalizing marijuana largely has been to allow states to implement

their own laws on the drug. DOJ has nonetheless reaffirmed that marijuana growth, possession,

and trafficking remain crimes under federal law irrespective of states’ marijuana laws. Federal

law enforcement has generally focused its efforts on criminal networks involved in the illicit

marijuana trade. Federal banking regulators have yet to issue any formal guidance in response to

state and local marijuana legalization efforts; however, in February 2014 the Treasury

Department’s Financial Crimes Enforcement Network (FinCEN) issued guidance on financial

institutions’ suspicious activity report requirements when serving marijuana businesses.

122 Any interested party may petition the Administrator of DEA to initiate rulemaking proceedings to reschedule a

controlled substance. See 21 U.S.C. Section 811(a) and 21 C.F.R. Section 1308.43(a) for relevant rules and regulations.

123 In 2011, the governors of Rhode Island and Washington jointly petitioned DEA to have marijuana and “related

items” removed from Schedule I of the CSA and rescheduled as medical cannabis in Schedule II. In 2009, Bryan

Krumm, a health provider in New Mexico, petitioned DEA to have marijuana removed from Schedule I of the CSA and

rescheduled in any schedule other than Schedule I.

124 DEA has previously denied petitions to reschedule marijuana. For example, in 2002 a petition was filed to have

marijuana removed from Schedule I and rescheduled as cannabis in Schedule III, IV, or V. In 2011, DEA rejected the

petition. See DOJ, DEA, “Denial of Petition to Initiate Proceedings to Reschedule Marijuana,” 76 Federal Register

40552-40589, July 8, 2011.

125 See DOJ, DEA, “Denial of Petition to Initiate Proceedings to Reschedule Marijuana,” 81 Federal Register 5376753845, August 12, 2016; and DOJ, DEA, “Denial of Petition to Initiate Proceedings to Reschedule Marijuana,” 81

Federal Register 53687-53766, August 12, 2016.

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Federalism: Federal Preemption and the Anti-Commandeering

Doctrine126

The gap between the federal CSA,127 which criminalizes the cultivation, distribution, and

possession of marijuana, and certain state marijuana laws, which authorize some of those same

activities, raises questions regarding “the proper division of authority between the Federal

Government and the States”128 under both the preemption and anti-commandeering doctrines. The

Supremacy Clause of the U.S. Constitution generally establishes that federal law is supreme to,

and may preempt, conflicting state laws.129 However, the federal government’s preemptive

authority is subject to certain limitations, including the anti-commandeering doctrine, which

generally prohibits the federal government from forcing states to perform regulatory activities on

the federal government’s behalf.130 See Appendix E for a comprehensive legal discussion of the

federal preemption and anti-commandeering doctrines, and how the courts have handled the

conflict between federal CSA and state marijuana laws.

Enforcement Focused on Traffickers

Federal law enforcement generally focuses its counterdrug efforts on criminal networks involved

in the illicit drug trade. Federal marijuana enforcement efforts, largely focused on traffickers and

distributors of marijuana rather than users, appear to be consistent with this position.131 Arrests

for marijuana possession offenses are largely made by state and local police.132 President Barack

Obama once noted that “[it] would not make sense from a prioritization point of view for us to

focus on recreational drug users in a state that has already said that under state law

that’s legal.”133 Officials in the Trump Administration also indicated that prosecuting traffickers

over users was a priority; and while there was some uncertainty about the future of marijuana

policy under the Trump Administration, then-Attorney General Sessions noted that federal law

126 This section was authored by David H. Carpenter, Legislative Attorney in CRS’s American Law Division (ALD). It

uses citation and other editorial styles consistent with ALD’s reports.

127 Comprehensive Drug Abuse Prevention and Control Act of 1970, Pub. L. No. 91-513, Title II, 84 Stat. 1236, 1242

(codified as amended at 21 U.S.C. §§ 801–904).

128 New York v. United States, 505 U.S. 144, 149 (1992).

129 U.S. CONST. art. VI, cl. 2.

130 Murphy v. NCAA, 138 S. Ct. 1461, 1476 (2019) (“The legislative powers granted to Congress are sizable, but they

are not unlimited. The Constitution confers on Congress not plenary legislative power but only certain enumerated

powers. Therefore, all other legislative power is reserved for the States, as the Tenth Amendment confirms. And

conspicuously absent from the list of powers given to Congress is the power to issue direct orders to the governments

of the States. The anticommandeering doctrine simply represents the recognition of this limit on congressional

authority.”).

131 DEA’s mission “is to enforce the controlled substances laws and regulations of the United States and bring to the

criminal and civil justice system of the United States, or any other competent jurisdiction, those organizations and

principal members of organizations, involved in the growing, manufacture, or distribution of controlled substances

appearing in or destined for illicit traffic in the United States; and to recommend and support non-enforcement

programs aimed at reducing the availability of illicit controlled substances on the domestic and international markets.”

See https://www.dea.gov/mission.

132 In 2015, the Government Accountability Office concluded that DOJ has not historically targeted possession of small

amounts of marijuana for personal use on private property, and has left lower-level marijuana activity to state and local

law enforcement authorities through enforcement of their own drug laws. See U.S. Government Accountability Office

(GAO), State Marijuana Legalization: DOJ Should Document Its Approach to Monitoring the Effects of Legalization,

GAO-16-1, December 2015, p. 9.

133 “Marijuana Not High Obama Priority,” ABC Nightline, December 14, 2012.

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enforcement would continue to focus their marijuana-related enforcement efforts on criminal

organizations over “routine cases.”134 Similarly, then-Attorney General Barr noted he would

continue to “prioritize the prosecution of significant drug traffickers, rather than drug users or

low-level drug offenders.”135 During his 2021 Senate confirmation hearing, Attorney General

Garland indicated that the Biden Administration will maintain this position.136

Department of Justice Guidance Memos for U.S. Attorneys

DOJ has articulated federal marijuana enforcement policy through several memoranda providing

direction for U.S. Attorneys in states that have medical use of marijuana programs. After states

began to legalize the medical use of marijuana, DOJ reaffirmed that marijuana growth,

possession, and trafficking remain crimes under federal law irrespective of state law.137 In 2009,

former Deputy Attorney General David Ogden authored a memo for selected U.S. Attorneys that

reiterated that combating major drug traffickers remains a central priority and stated:

[t]he prosecution of significant traffickers of illegal drugs, including marijuana, and the

disruption of illegal drug manufacturing and trafficking networks continues to be a core

priority in the [Justice] Department’s efforts against narcotics and dangerous drugs, and

the Department’s investigative and prosecutorial resources should be directed towards

these objectives. As a general matter, pursuit of these priorities should not focus federal

resources in your States on individuals whose actions are in clear and unambiguous

compliance with existing state laws providing for the medical use of marijuana. 138

In a follow-up memorandum to U.S. Attorneys in 2011, former Deputy Attorney General James

Cole restated that enforcing the CSA remained a core priority of DOJ, even in states that had

legalized medical marijuana. He clarified that “[t]he Ogden Memorandum was never intended to

shield such activities from federal enforcement action and prosecution, even where those

activities purport to comply with state law.”139 Deputy Attorney General Cole warned those who

might assist medical marijuana dispensaries in any way that “[p]ersons who are in the business of

cultivating, selling or distributing marijuana, and those who knowingly facilitate such activities

[emphasis added], are in violation of the Controlled Substances Act, regardless of state law.”140

This has been interpreted by some to mean, for example, that building owners and managers are

in violation of the CSA if they allow medical marijuana dispensaries to operate in their

134 Remarks by Attorney General Jeff Sessions at a Georgetown Law student symposium hosted by the Federalist

Society, March 10, 2018, https://www.c-span.org/video/?442403-1/attorney-general-jeff-sessions-judicial-authority. He

stated that federal law enforcement would not be able to, even if it wished to, take over “state enforcement of routine

[marijuana] cases.”

135 William P. Barr, “Questions for the Record, William P. Barr, Nominee to be United States Attorney General,”

January 27, 2019.

136 U.S. Congress, Senate Committee on the Judiciary, The Nomination of the Honorable Merrick Brian Garland to be

Attorney General of the United States: Responses to Questions for the Record to Judge Merrick Garland, Nominee to

be United States Attorney General, 117th Cong., 1st sess., February 2021, pp. 23-25.

137 United States Attorney’s Office, “Statement From U.S. Attorney’s Office on Initiative 502,” press release,

December 5, 2012.

138 Deputy Attorney General David W. Ogden, Memorandum for Selected United States Attorneys, U.S. Department of

Justice, Investigations and Prosecutions in States Authorizing the Medical Use of Marijuana, Washington, DC, October

19, 2009, pp. 1-2.

139 Deputy Attorney General James M. Cole, Memorandum for United States Attorneys, U.S. Department of Justice,

Guidance Regarding the Ogden Memo in Jurisdictions Seeking to Authorize Marijuana for Medical Use, Washington,

DC, June 29, 2011, p. 2.

140 Ibid.

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buildings.141 Deputy Attorney General Cole further warned that “[t]hose who engage in

transactions involving the proceeds of such activity [cultivating, selling, or distributing of

marijuana] may be in violation of federal money laundering statutes and other federal financial

laws.”142

In an August 2013 memorandum (the Cole memorandum), Deputy Attorney General Cole stated

that while marijuana remains an illegal substance under the CSA, DOJ would focus its resources

on the “most significant threats in the most effective, consistent, and rational way,” and outlined

eight marijuana enforcement priorities for DOJ: 143





preventing the distribution of marijuana to minors;

preventing revenue from the sale of marijuana from going to criminal enterprises,

gangs, and cartels;



preventing the diversion of marijuana from states where it is legal under state law

in some form to other states;

preventing state-authorized marijuana activity from being used as a cover or

pretext for the trafficking of other illegal drugs or other illegal activity;

preventing violence and the use of firearms in the cultivation and distribution of

marijuana;











preventing drugged driving and the exacerbation of other adverse public health

consequences associated with marijuana use;

preventing the growing of marijuana on public lands and the attendant public

safety and environmental dangers posed by marijuana production on public

lands; and

preventing marijuana possession or use on federal property.144

In a February 2014 memorandum, Deputy Attorney General Cole further reinforced these

enforcement priorities, specifically as they related to the prosecution of marijuana-related

financial crimes. This memorandum directed the U.S. Attorneys that “in determining whether to

charge individuals or institutions with ... [certain financial] offenses based on marijuana-related

violations of the CSA, prosecutors should apply the eight enforcement priorities described in the

August 29 guidance.”145

In October 2014, DOJ released another memorandum to the U.S. Attorneys that asserted the

applicability of the eight enforcement priorities in Indian Country.146 It responded to the tribes’

requests for guidance on CSA enforcement on tribal lands. DOJ reiterated that the 2013 Cole

141 Jennifer Medina, “U.S. Attorneys in California Set Crackdown on Marijuana,” New York Times, October 8, 2011, p.

10.

142 Deputy Attorney General James M. Cole, Memorandum for United States Attorneys, U.S. Department of Justice,

Guidance Regarding the Ogden Memo in Jurisdictions Seeking to Authorize Marijuana for Medical Use, Washington,

DC, June 29, 2011, p. 2.

143 Deputy Attorney General James M. Cole, Memorandum for all United States Attorneys, U.S. Department of Justice,

Guidance Regarding Marijuana Enforcement, Washington, DC, August 29, 2013, p. 1.

144 Ibid., pp. 1-2.

145 Deputy Attorney General James M. Cole, Memorandum for All United States Attorneys, U.S. Department of Justice,

Guidance Regarding Marijuana Related Financial Crimes, Washington, DC, February 14, 2014, p. 2.

146 Executive Office for United States Attorneys, Policy Statement Regarding Marijuana Issues in Indian Country,

October 28, 2014.

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memorandum did not prohibit the federal government from enforcing federal law in Indian

Country, and added the following:

The eight priorities in the Cole Memorandum will guide United States Attorneys’

marijuana enforcement efforts in Indian Country, including in the event that sovereign

Indian Nations seek to legalize the cultivation or use of marijuana in Indian Country

[emphasis added].147

Unlike the Cole memorandum, DOJ did not specifically refer to distribution and regulation of

marijuana. It was unclear whether distribution of marijuana would be tolerated on tribal lands

should tribal governments seek to legalize and distribute marijuana. Despite the lack of clarity,

some tribes moved forward with plans to grow and sell marijuana at tribe-owned stores on tribal

lands.148 Since the memo was released, DEA has led some marijuana enforcement actions on

tribal lands involving tribe-authorized marijuana activity.149

In January 2018, DOJ issued another memorandum (Sessions memorandum) to the U.S.

Attorneys on marijuana enforcement. In it, then-Attorney General Sessions emphasized the CSA

prohibition of marijuana cultivation, distribution, and possession and its associated penalties. He

also pointed out that these marijuana activities may “serve as the basis for the prosecution of

other crimes, such as those prohibited by the money laundering statutes, the unlicensed money

transmitter statute, and the Bank Secrecy Act…. [T]hese statutes reflect Congress’s determination

that marijuana is a dangerous drug and that marijuana activity is a serious crime.”150 Sessions also

noted in the memorandum that DOJ had “well-established principles” dating back to 1980 to

decide which marijuana activities to prosecute, and because these principles exist, the previous

DOJ memoranda were unnecessary and rescinded.151

While DOJ has not released additional memoranda on marijuana enforcement since the Sessions

memorandum, then-Attorney General Barr indicated his discomfort with “ignoring the

enforcement of federal law.”152 On the other hand, Barr also stated during his nomination hearing

that he did not intend to target marijuana businesses that had relied on the Cole memorandum for

guidance.153 Attorney General Garland stated the following in his official responses to questions

147 Monty Wilkinson, Memorandum, U.S. Department of Justice, Policy Statement Regarding Marijuana Issues in

Indian Country, Washington, DC, October 28, 2014.

148 “Native American Tribes Approve Plan to Grow and Sell Marijuana in Oregon,” The New York Times, December

19, 2015; Jackie Valley, “Las Vegas Paiutes’ Newest Venture: Medical Marijuana,” Las Vegas Sun, March 1, 2016;

Noelle Crombie, “Warm Springs Tribes Launch Ambitious Pot Venture, Hope for Economic Windfall,” The Oregonian

- Oregon Live, April 29, 2016; John Gillie, “Two Marijuana Retailers Opening Soon in City that Still Bans Cannabis

Sales,” The News Tribune, January 28, 2017; Saint Regis Mohawk Tribal Council, Tribal Election Board Certifies

Medical Marijuana Ordinance and Adult Use (Recreational) Marijuana Referendum Results, December 23, 2019,

https://www.srmt-nsn.gov/; and Dalton Walker, “Red Lake Nation approves medical cannabis,” Red Lake Nation News,

May 29, 2020.

149 Steven Nelson, “DEA Raid on Tribe’s Cannabis Crop Infuriates and Confuses Reformers,” U.S. News & World

Report, October 26, 2015; and Cary Spivak, “Milwaukee Journal Sentinel,” November 18, 2015.

150 Attorney General Jefferson B. Sessions, Memorandum for All United States Attorneys, U.S. Department of Justice,

Marijuana Enforcement, Washington, DC, January 4, 2018.

151 Ibid.

152 See comments made by former Attorney General Barr in response to questioning from Senator Murkowski, U.S.

Congress, Senate Committee on Appropriations, Subcommittee on Commerce, Justice, Science, and Related Agencies,

Hearing to review the Fiscal Year 2020 funding request and budget justification for the U.S. Department of Justice,

116th Cong., 2nd sess., April 10, 2019.

153 See comments made by former Attorney General Barr in response to questioning from Senator Booker, U.S.

Congress, Senate Committee on the Judiciary, Nomination of the Honorable William Pelham Barr to be Attorney

General of the United States, 116th Cong., 1st sess., January 15, 2019.

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from his Senate confirmation hearing: “I do not think it the best use of the Department’s [DOJ’s]

limited resources to pursue prosecutions of those who are complying with the laws in states that

have legalized and are effectively regulating marijuana.”154

Monitoring Enforcement Priorities

In a 2015 review of the DOJ memoranda and evaluation of DOJ efforts to monitor effects of state

legalization relative to DOJ guidance (which predated the Sessions memorandum), the

Government Accountability Office (GAO) concluded that “DOJ has not historically devoted

resources to prosecuting individuals whose conduct is limited to possession of small amounts of

marijuana for personal use on private property. Rather, DOJ has left such lower-level or localized

marijuana activity to state and local law enforcement authorities through enforcement of their

own drug laws.”155 GAO recommended that DOJ monitor the effects of state-level marijuana

legalization initiatives relative to the eight DOJ enforcement priorities outlined in the Cole

memorandum. GAO’s evaluation noted that DOJ was already taking a number of steps to help

assess these effects. For instance, DOJ indicated that U.S. Attorneys were in contact with officials

in states that had legalized marijuana, and through these interactions could communicate federal

enforcement priorities, assess the implications of legalization relative to the priorities, and

identify specific areas of federal concern. In addition, DOJ reported that it relies upon information

from sources such as “federal surveys on drug use; state and local research; and feedback from

federal, state, and local law enforcement” to assess the effects of state-level legalization

initiatives.156 GAO concluded that DOJ had not documented its specific monitoring process, and

recommended that DOJ develop a “clear plan” for how it will monitor and document the effects

of state marijuana legalization on federal enforcement priorities.157 Since the Sessions

memorandum rescinded the previous DOJ guidance memos (which included the enforcement

priorities GAO focused on), DOJ has not indicated whether it monitors and documents the effects

of state marijuana legalization on federal enforcement priorities.

Limiting Federal Enforcement in States: Directives through Federal

Appropriations158

In each fiscal year since FY2015, Congress has included provisions in appropriations acts that

prohibit DOJ from using appropriated funds to prevent certain states and territories and the

District of Columbia from “implementing their own laws that authorize the use, distribution,

possession, or cultivation of medical marijuana.”159

154 U.S. Congress, Senate Committee on the Judiciary, The Nomination of the Honorable Merrick Brian Garland to be

Attorney General of the United States: Responses to Questions for the Record to Judge Merrick Garland, Nominee to

be United States Attorney General, 117th Cong., 1st sess., February 2021, pp. 23-25.

155 U.S. Government Accountability Office, State Marijuana Legalization: DOJ Should Document Its Approach to

Monitoring the Effects of Legalization, GAO-16-1, December 2015, p. 9.

156 Ibid., p. 27.

157 Ibid.

158 This section was authored by Joanna Lampe, Legislative Attorney in CRS’s American Law Division (ALD). It uses

citation and other editorial styles consistent with ALD’s reports.

159 See Consolidated and Further Continuing Appropriations Act, 2015, P.L. 113-235 (113th Cong. 2014); Consolidated

Appropriations Act, 2016, P.L. 114-113 (114th Cong. 2015); Consolidated Appropriations Act, 2017, P.L. 115-31

(115th Cong. 2017); Consolidated Appropriations Act, 2018, P.L. 115-141 (115th Cong. 2018); Consolidated

Appropriations Act, 2019, P.L. 116-6 (116th Cong. 2019); Consolidated Appropriations Act, 2020, P.L. 116-93 (116th

Cong. 2019); Consolidated Appropriations Act, 2021, P.L. 116-260 (116th Cong. 2020); and Consolidated

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On its face, the appropriations rider bars DOJ from taking legal action against the states directly

in order to prevent them from promulgating or enforcing medical marijuana laws.160 In addition,

federal courts have interpreted the rider to prohibit certain federal prosecutions of private

individuals or organizations that produce, distribute, or possess marijuana in accordance with

state medical marijuana laws. In the 2016 case United States v. McIntosh, the U.S. Court of

Appeals for the Ninth Circuit held that the rider

prohibits the federal government only from preventing the implementation of those specific

rules of state law that authorize the use, distribution, possession, or cultivation of medical

marijuana. DOJ does not prevent the implementation of [such rules] when it prosecutes

individuals who engage in conduct unauthorized under state medical marijuana laws.

Individuals who do not strictly comply with all state-law conditions regarding the use,

distribution, possession, and cultivation of medical marijuana have engaged in conduct that

is unauthorized, and prosecuting such individuals does not violate [the rider].161

The Ninth Circuit has issued several decisions allowing federal prosecution of individuals who

did not strictly comply with state medical marijuana laws, notwithstanding the appropriations

rider, and several district courts have followed that holding.162

In the 2022 case United States v. Bilodeau, the U.S. Court of Appeals for the First Circuit agreed

with the Ninth Circuit that the rider means “DOJ may not spend funds to bring prosecutions if

doing so prevents a state from giving practical effect to its medical marijuana laws.”163 However,

the First Circuit declined to adopt the Ninth Circuit’s holding that a defendant must demonstrate

strict compliance with state law before the rider bars prosecution.164 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.”165 Thus, the court 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.166 The court further held, however, that it would not have any effect

on Maine’s medical marijuana laws to prosecute “the defendants’ cultivation, possession, and

distribution of marijuana aimed at supplying persons whom no defendant ever thought were

qualifying patients under Maine law.”167

Appropriations Act, 2022, P.L. 117-103 (117th Cong. 2022) . The FY2022 provision lists 52 jurisdictions, including

most of the states, the District of Columbia, the Commonwealth of the Northern Mariana Islands, Guam, Puerto Rico,

and the U.S. Virgin Islands. Continuing resolutions used to cover gaps in enacted funding for DOJ have extended the

provision. See, e.g., Continuing Appropriations Act, 2021 and Other Extensions Act, P.L. 116-159 (116th Cong. 2020).

160 Cf. United States v. Marin All. for Med. Marijuana, 139 F. Supp. 3d 1039, 1044 (E.D. Cal. 2015) (citing DOJ’s

interpretation that the appropriations rider prohibits “federal actions that interfere with a state’s promulgation of

regulations implementing its statutory provisions, or with its establishment of a state licensing scheme”).

161 United States v. McIntosh, 833 F.3d 1163, 1178 (9th Cir. 2016).

162 United States v. Evans, 929 F.3d 1073, 1078-79 (9th Cir. 2019); United States v. Kleinman, 880 F.3d 1020, 1027-30

(9th Cir. 2017); Duval v. United States, 372 F. Supp. 3d 544, 555-56 (E.D. Mich. 2019); United Sates v. Bloomquist,

361 F. Supp. 3d 744, 749-51 (W.D. Mich. 2019); United States v. Jackson, 2019 WL 3239844 at *6-8 (E.D. Pa. June 5,

2019).

163 2022 WL 225333 at *5 (1st Cir. Jan. 26, 2022).

164 Id.

165 Id.

166 Id. While the court held that something less than strict compliance was required to avoid prosecution under the rider,

it declined to “fully define [the] precise boundaries” of its alternative standard. Id. at *6.

167 Id. at *6.

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It remains to be seen whether and how the difference in reasoning between the Ninth Circuit and

the First Circuit will make a practical difference in federal marijuana prosecutions. In theory, the

First Circuit’s analysis could make it easier for defendants to invoke the appropriations rider to

bar prosecutions. In practice, however, resource limitations and enforcement priorities have

historically meant that federal marijuana prosecutions target individuals and organizations that

clearly have not complied with state law.168 Thus, one of the judges in 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.”169

Marijuana-related activities that fall outside the scope of the appropriations rider remain subject

to prosecution under the CSA.170 By its terms, the rider applies only to state laws related to

medical marijuana; it does not bar prosecution of any activities related to recreational marijuana,

even if those activities are permitted under state law.171 In addition, although the appropriations

rider restricts DOJ’s ability to expend funds to enforce federal law for as long as it remains in

effect, the rider “does not provide immunity from prosecution for federal marijuana offenses.”172

Congress could repeal the rider at any time or could decline to include it in future appropriations

laws. If Congress were to repeal the rider or allow it to lapse, DOJ would be able to prosecute

future CSA violations as well as violations that occurred while the rider was in effect, subject to

the applicable statute of limitations.173 In the alternative, Congress could expand the scope of the

rider to include recreational marijuana or other controlled substances. Regardless of whether they

are subject to criminal prosecution, participants in the cannabis industry may face numerous

collateral consequences arising from the federal prohibition of marijuana.174

168 See, e.g., id. at *9 (Barron, J., concurring).

169 Id.

170 Cf. United States v. Nixon, 839 F.3d 885, 886 (9th Cir. 2016) (per curiam) (holding that the appropriations rider does

not “impact[ ] the ability of a federal district court to restrict the use of a medical marijuana as a condition of

probation”); Sandusky v. Herrera, 2020 WL 2129212 at *4 (D. Colo. May 5, 2020) (dismissing as moot a habeas claim

from an individual subject to supervised release following conviction for a marijuana offense because the U.S.

Probation Office is not part of DOJ and “[t]he appropriations rider, by its plain language, does not apply to the federal

courts”).

171 In practice, 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.” U.S. Government Accountability Office, State Marijuana Legalization: DOJ

Should Document Its Approach to Monitoring the Effects of Legalization, GAO-16-1, 9 (Dec. 2015); but cf.

Memorandum from Jefferson B. Sessions, Attorney Gen., U.S. Dep’t of Justice, on Marijuana Enforcement to all

United States Attorneys (Jan. 4, 2018), https://www.justice.gov/opa/press-release/file/1022196/download (reaffirming

the authority of federal prosecutors to exercise prosecutorial discretion to target federal marijuana offenses “in

accordance with all applicable laws, regulations, and appropriations”).

172 United States v. McIntosh, 833 F.3d 1163, 1179 n.5 (9th Cir. 2016).

173 Id.

174 For additional information about the collateral consequences of marijuana-related activities, see the “Marijuana

Policy Gap” section of CRS Report R45948, The Controlled Substances Act (CSA): A Legal Overview for the 117th

Congress, by Joanna R. Lampe.

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Federal Financial Laws and Financial Services for Marijuana

Businesses175

Because marijuana is a Schedule I controlled substance under the CSA,176 financial institutions

and their directors, officers, employees, and owners might be subject to criminal and

administrative sanctions177 for providing financial services to marijuana businesses, even if those

marijuana businesses operate in states that have legalized certain marijuana-related activities.178

Although DOJ and FinCEN have issued guidance on the interplay of federal marijuana laws and

discordant state legalization efforts, many financial institutions have been unwilling to provide

financial services to state-authorized marijuana businesses because of the legal risks under federal

law.179

Bank Secrecy Act180 and Federal Anti-Money Laundering Laws

Financial institutions generally do not sell, possess, or distribute the products or assets of their

financial services customers.181 Consequently, auxiliary liability (e.g., aiding and abetting,

175 This section was authored by David H. Carpenter, Legislative Attorney in CRS’s American Law Division (ALD). It

uses citation and other editorial styles consistent with ALD’s reports.

176 For legal discussion of the CSA, see CRS Report R45948, The Controlled Substances Act (CSA): A Legal Overview

for the 117th Congress.

177 See, e.g., United States v. HSBC Bank USA, N.A., No. 12-CR-763, 2013 U.S. Dist. LEXIS 92438, 31–38 (E.D.

N.Y. July 1, 2013) (approving a deferred prosecution agreement with a financial institution for, among other things,

“fail[ing] to implement an effective [anti-money laundering] program to monitor suspicious transactions ... [which]

permitted Mexican and Colombian drug traffickers to launder at least $881 million in drug trafficking proceeds through

HSBC Bank USA undetected”; the agreement “imposes upon HSBC significant, and in some respect extraordinary,

measures,” including forfeiture of $1.256 billion, remedial measures, and the admission of criminal violations).

178 United States v. McIntosh, 833 F.3d 1163, 1179 n.5 (9th. Cir 2016) (“The prior observation should also serve as a

warning. To be clear, § 542 [of the Consolidated Appropriations Act, 2016, Pub. L. No. 114–113, 129 Stat. 2242,

2332–33 (2015)] does not provide immunity from prosecution for federal marijuana offenses. The CSA prohibits the

manufacture, distribution, and possession of marijuana. Anyone in any state who possesses, distributes, or

manufactures marijuana for medical or recreational purposes (or attempts or conspires to do so) is committing a federal

crime. The federal government can prosecute such offenses for up to five years after they occur. See 18 U.S.C. § 3282.

Congress currently restricts the government from spending certain funds to prosecute certain individuals. But Congress

could restore funding tomorrow, a year from now, or four years from now, and the government could then prosecute

individuals who committed offenses while the government lacked funding. Moreover, ... a new administration could

shift enforcement priorities to place greater emphasis on prosecuting marijuana offenses.”).

179 See, e.g., Guidance on Provision of Financial Services to Medical Marijuana & Industrial Hemp-Related

Businesses in New York State, N.Y. DEP’T OF FIN. SERVS., 2 (Jul. 3, 2018), https://www.dfs.ny.gov/docs/legal/industry/

il180703.pdf (“Because marijuana currently is still listed on Schedule I under the Federal Controlled Substances Act,

medical marijuana ... businesses operating in accordance with New York State laws and regulations continue to have

difficulty establishing banking relationships at regulated financial institutions. The ability to establish a banking

relationship is an urgent issue today for the legal cannabis industry. So long as it remains difficult to open and maintain

bank accounts, the industry will largely rely on cash to conduct business and operate.”).

180 The “Bank Secrecy Act” is commonly used to refer to Titles I and II of Pub. L. No. 91-508 and includes the

Currency and Foreign Transactions Reporting Act, Pub. L. No. 91-508, Title II, 84 Stat. 1114, 1118–24 (1970) (as

amended and codified at 12 U.S.C. §§ 1829b, 1951–59; 31 U.S.C. §§ 5311–32). The Bank Secrecy Act requires reports

and records of transactions involving cash, negotiable instruments, or foreign currency and authorizes the Secretary of

the Treasury to prescribe regulations to insure that adequate records are maintained of transactions that have a “high

degree of usefulness in criminal, tax, or regulatory investigations or proceedings.” Id.

181 Financial institutions do, at times, take legal possession of their clients’ assets, such as after a customer defaults on a

loan secured by real property or business inventory.

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conspiracy)182 aside, financial services institutions generally would not engage directly in actions

barred by the CSA. However, financial institutions commonly acquire proceeds generated by

their customers’ product sales. As described below, financial institutions that acquire proceeds

generated by marijuana businesses could be subject to civil and criminal asset forfeiture,

prosecution under the Bank Secrecy Act and criminal anti-money laundering laws, and

administrative enforcement actions.183

Federal law authorizes the seizure of property connected to unlawful marijuana activity through

civil and criminal asset forfeiture proceedings. Consequently, federal authorities could potentially

confiscate funds a bank acquires from marijuana businesses that are derived from the proceeds of

marijuana sales,184 even if state law permits those sales.185 For example, if a bank lends to a stateauthorized medical marijuana dispensary, federal authorities might be able to require the bank to

forfeit loan payments the dispensary makes to the bank on the grounds that such payments can be

traced to federally prohibited marijuana sales.186

In addition to the risk of asset forfeiture, federal anti-money laundering (AML) laws (i.e.,

Sections 1956 and 1957 of the criminal code) criminalize the handling of financial proceeds that

are known to be derived from certain unlawful activities,187 including selling and distributing

marijuana.188 Violators of anti-money laundering laws may be subject to fines and

imprisonment,189 and any real or personal property involved in or traceable to prohibited

transactions is potentially subject to civil or criminal forfeiture.190 For example, a bank employee

could be subject to a twenty-year prison sentence and criminal fines under Section 1956 for

knowingly engaging in a financial transaction involving marijuana-related proceeds with the

intent to promote a further offense, such as withdrawing funds generated from marijuana sales

from a business checking account to pay the salaries of medical marijuana dispensary

employees.191 Similarly, a bank officer could face a ten-year prison term and criminal fines under

Section 1957 for knowingly receiving deposits or allowing withdrawals of $10,000 or more in

cash that is derived from distributing and selling marijuana.192

182 18 U.S.C. § 2 (aiding and abetting); 21 U.S.C. § 846 (conspiracy under the CSA).

183 See, e.g., 12 U.S.C. § 1818; 18 U.S.C. § 981(a)(1), 1956, 1957.

184 18 U.S.C. § 981(a)(1) (“The following property is subject to forfeiture to the United States ... (C) Any property, real

or personal, which constitutes or is derived from proceeds traceable to ... any offense constituting ‘specified unlawful

activity’ (as defined in section 1956(c)(7) of this title) [i.e., the list of predicate offenses for money laundering (18

U.S.C. § 1956)], or a conspiracy to commit such offense.”).

185 United States v. McIntosh, 833 F.3d 1163, 1179 n.5 (9th Cir. 2016).

186 21 U.S.C. §§ 853, 881.

187 18 U.S.C. §§ 1956(c)(7), 1957(f)(3). See “Specified Unlawful Activities” in CRS Report RL33315, Money

Laundering: An Overview of 18 U.S.C. § 1956 and Related Federal Criminal Law (providing a full list of predicate

offenses).

188

18 U.S.C. §§ 1956, 1957. See CRS Report RL33315, Money Laundering: An Overview of 18 U.S.C. § 1956 and

Related Federal Criminal Law (providing a detailed analysis of federal anti-money laundering laws).

189 Section 1956 violations are punishable by imprisonment for not more than twenty years and fines of up to $500,000

or twice the value of the property involved, whichever is greater. 18 U.S.C. § 1956(a)(1). Section 1957 violations are

punishable by imprisonment for not more than ten years and fines of up $250,000 (or $500,000 for organizations) or

twice the value of the property involved in the transaction, whichever is greater. Id. §§ 1957(b), 3571, 3559.

Conspiracy to violate either section carries the same maximum penalties, as does aiding and abetting the commission of

either offense. Id. §§ 2, 1956(h). See, e.g., United States v. Lyons, 740 F.3d 702, 715 (1 st Cir. 2014).

190 18 U.S.C. §§ 981(a)(1)(A), 982(a)(1).

191 Id. § 1956(a)(1)(A)(i).

192 Id. § 1957(a), (d).

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Moreover, federal law requires financial institutions193 to aid law enforcement in investigating

and prosecuting those who violate federal laws, including the CSA.194 For example, the Secretary

of the Treasury has exercised authority to require financial institutions to file suspicious activity

reports (SARs)195 with FinCEN regarding financial transactions196 suspected to be derived from

illegal activities,197 including marijuana sales.198 Depository institutions and certain other

financial institutions199 also must establish and maintain AML programs. AML programs are

designed to prevent financial institutions from facilitating money laundering and financing

terrorist activity, as well as to ensure that the institutions’ officers and employees have sufficient

knowledge of their customers and their customers’ businesses to identify when filing SARs is

appropriate.200 Additionally, federal regulators can subject financial institutions, their employees,

and certain affiliated parties201 to administrative enforcement actions for violating the Bank

193 For the purposes of the Bank Secrecy Act and anti-money laundering laws, the term “financial institution” is defined

broadly to include banks, savings associations, credit unions, broker dealers, insurance companies, pawnbrokers,

automobile dealers, casinos, cash checkers, travel agencies, and precious metal dealers, among others. 31 U.S.C. §

5312(a)(2).

194 12 U.S.C. §§ 1951–59; 31 U.S.C. §§ 5311–32.

195 31 U.S.C. § 5318(g). Filing suspicious activity reports (SARs) are mandatory under certain circumstances, but

financial institutions may file SARs even when not mandated by law. See, e.g., 12 C.F.R. §§ 1020.320(a) (banks); 31

CFR § 1022.320(a) (money services businesses).

196 “Transaction” is defined as:

means a purchase, sale, loan, pledge, gift, transfer, delivery, or other disposition, and with respect to

a financial institution includes a deposit, withdrawal, transfer between accounts, exchange of

currency, loan, extension of credit, purchase or sale of any stock, bond, certificate of deposit, or other

monetary instrument, security, contract of sale of a commodity for future delivery, option on any

contract of sale of a commodity for future delivery, option on a commodity, purchase or redemption

of any money order, payment or order for any money remittance or transfer, purchase or redemption

of casino chips or tokens, or other gaming instruments or any other payment, transfer, or delivery by,

through, or to a financial institution, by whatever means effected.

Id. § 1010.100(bbb).

197 18 U.S.C. §§ 1956(c)(7), 1957(f)(3). See “Specified Unlawful Activities” in CRS Report RL33315, Money

Laundering: An Overview of 18 U.S.C. § 1956 and Related Federal Criminal Law (providing a full list of predicate

offenses).

198 21 U.S.C. §§ 841

–90; 31 U.S.C. § 5318(g); 31 C.F.R. § 1020.320.

199 There are several different types of depository institutions, including state- and federally chartered banks, savings

associations, and credit unions.

200 See generally id. §§ 5318(h)(1), 1020.200–20. See also 12 U.S.C. § 1786(q)(1) (credit unions); id. § 1818(s) (banks

and savings associations). Even in the absence of suspicion, financial institutions must file currency transaction reports

(CTRs) with FinCEN relating to transactions involving $10,000 or more in cash or other “currency.” 31 U.S.C. § 5313;

31 C.F.R. §§ 1020.300–20, 1010.300–70. “Currency” is defined as:

The coin and paper money of the United States or of any other country that is designated as legal

tender and that circulates and is customarily used and accepted as a medium of exchange in the

country of issuance. Currency includes U.S. silver certificates, U.S. notes and Federal Reserve notes.

Currency also includes official foreign bank notes that are customarily used and accepted as a

medium of exchange in a foreign country.

Id. at § 1010.100(m).

The willful failure to file SARs and CTRs is punishable by imprisonment for not more than five years or not more than

ten years in cases of a substantial pattern of violations or transactions involving other illegal activity. 31 U.S.C. § 5322.

Structuring a transaction to avoid the reporting requirement exposes the offender to the same maximum terms of

imprisonment. Id. § 5324(d). See CRS Report RL33315, Money Laundering: An Overview of 18 U.S.C. § 1956 and

Related Federal Criminal Law (providing a detailed description of penalties for violations of Bank Secrecy Act

reporting and monitoring requirements).

201 See, e.g., 12 U.S.C. §§ 1813(u) (defining “institution-affiliated party” to include, among others, “any director,

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Secrecy Act or AML laws.202 For example, federal banking regulators203 implement

comprehensive supervisory regimes that are designed to ensure that depository institutions are

managed and operated safely and soundly to maintain financial stability and comply with

applicable state and federal law. To this end, banking regulators have strong, flexible

administrative enforcement powers, which they may use against depository institutions and their

directors, officers, controlling shareholders, employees, agents, and affiliates that act unlawfully,

including by engaging in marijuana-related activities that violate the CSA or anti-money

laundering laws.204 Banking regulators may, for instance, issue cease-and-desist orders, impose

civil money penalties, and issue removal and prohibition orders that temporarily or permanently

ban individuals from working for depository institutions.205 Banking regulators also have

authority, under certain circumstances, to revoke an institution’s federal deposit insurance and to

take control of and liquidate a depository institution.206 For example, a criminal conviction for

violating the Bank Secrecy Act or AML laws is an explicit ground for appointing the Federal

Deposit Insurance Corporation “as receiver [to] place the insured depository institution in

liquidation.”207

Because of these legal risks, many financial institutions are unwilling to provide financial

services to the marijuana industry, often leaving marijuana businesses unable to accept debit or

credit card payments, use electronic payroll services, maintain checking accounts, or use other

common banking services.208 Consequently, many marijuana businesses reportedly operate

exclusively in cash,209 raising concerns about, among other things, tax collection compliance and

public safety.210

officer, employee, or controlling stockholder ... of, or agent for, an insured depository institution,” as well as any

independent contractor ... who knowingly or recklessly participates in any violation of any law or regulation; any

breach of fiduciary duty; or any unsafe or unsound practice which caused or is likely to cause more than a minimal

financial loss to, or a significant adverse effect on, the insured depository institution.”).

202 See, e.g., 12 U.S.C. §§ 1786, 1818, 1831o.

203 For these purposes, the federal banking regulators are the Office of the Comptroller of the Currency (OCC) for

national banks and federal savings associations; the Board of Governors of the Federal Reserve System for domestic

operations of foreign banks and state-chartered banks that are members of the Federal Reserve System; the Federal

Deposit Insurance Corporation (FDIC) for state savings associations and state-chartered banks that are not members of

the Federal Reserve System; and the National Credit Union Administration (NCUA) for federally insured credit unions.

Id. §§ 1766, 1813(q). The Bureau of Consumer Financial Protection (CFPB) also has certain consumer compliance

regulatory authority over depository institutions. Id. §§ 5481–5603.

204 See, e.g., id. § 1786 (credit unions); id. §§ 1818, 1831o (banks and savings associations). See also Press Release,

Off. of the Comptroller of the Currency, OCC Assesses $2.5 Million Civil Money Penalty Against Gibraltar Private

Bank and Trust Company for Bank Secrecy Act Violations (Feb. 25, 2016), https://www.occ.gov/news-issuances/newsreleases/2016/nr-occ-2016-20.html (ordering the payment of a civil money penalty and remedial actions for allegedly

“fail[ing] to maintain an effective Bank Secrecy Act/Anti-Money Laundering (BSA/AML) compliance program.”).

205 See, e.g., 12 U.S.C. § 1786 (credit unions); id. §§ 1818, 1831o (banks and savings associations).

206 See, e.g., id. §§ 1786–87 (credit unions); id. §§ 1818, 1821, 1831o (banks and savings associations).

207 Id. § 1821(c)(5)(M), (d)(2)(E).

208 See, e.g., Guidance on Provision of Financial Services to Medical Marijuana & Industrial Hemp-Related

Businesses in New York State, N.Y. DEP’T OF FIN. SERVS., 2 (Jul. 3, 2018), https://www.dfs.ny.gov/legal/industry/

il180703.pdf (“Because marijuana currently is still listed on Schedule I under the Federal Controlled Substances Act,

medical marijuana ... businesses operating in accordance with New York State laws and regulations continue to have

difficulty establishing banking relationships at regulated financial institutions. The ability to establish a banking

relationship is an urgent issue today for the legal cannabis industry. So long as it remains difficult to open and maintain

bank accounts, the industry will largely rely on cash to conduct business and operate.”).

209 Id.

210 See Tom Angell, Trump Treasury Secretary Wants Marijuana Money in Banks, FORBES (Feb. 6, 2018),

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The Evolution of Marijuana as a Controlled Substance and the Federal-State Policy Gap

FinCEN Guidance to Financial Institutions

In response to state and local marijuana legalization efforts, FinCEN issued guidance on

marijuana-related financial crimes to advise financial institutions on SAR reporting requirements

when serving marijuana businesses operating in compliance with state or local laws.211 The

guidance identified transactions that might trigger federal enforcement priorities,212 noting:

Because federal law prohibits the distribution and sale of marijuana, financial transactions

involving a marijuana-related business would generally involve funds derived from illegal

activity. Therefore, a financial institution is required to file a SAR on activity involving a

marijuana-related business (including those duly licensed under state law), in accordance

with this guidance and [FinCEN regulations]. 213

FinCEN also advised financial institutions serving marijuana businesses to file SARs under the

following conditions:







A marijuana limited SAR should be filed when a financial institution

determines, after exercising due diligence, that a marijuana-related business for

which the institution is providing financial services is not engaged in any

activities that violate state law or implicate the investigation and prosecution

priorities outlined in the guidance, including distributing to minors and

supporting drug cartels or similar criminal enterprises;214

A marijuana priority SAR should be filed when a financial institution believes

a marijuana-related business for which the institution is providing financial

services is engaged in activities that implicate prosecution priorities;215 and

A marijuana termination SAR should be filed when a financial institution finds

it must sever its relationship with a marijuana-related business to maintain an

effective AML program.216

The FinCEN guidance also lists examples of red flags that may indicate that a marijuana priority

SAR is appropriate.217

As of September 30, 2021 FinCEN reported that it has received 219,097 marijuana-related SARs

and that 755 depository institutions reported providing some form of financial services to

marijuana-related businesses.218 However, the depth and breadth of financial services that

https://www.forbes.com/sites/tomangell/2018/02/06/trump-treasury-secretary-wants-marijuana-money-in-banks/

#3c9bc4ed3a53.

211 FinCEN Marijuana Guidance 2014, supra note 182. Although DOJ rescinded several marijuana-related guidance

documents, FinCEN’s guidance remains in effect. The Administration could reverse or otherwise make significant

changes to its enforcement priorities and policies. See generally CRS Report R43708, The Take Care Clause and

Executive Discretion in the Enforcement of Law.

212 FinCEN Marijuana Guidance 2014, supra note 182.

213 Id. at 3.

214 Id. at 3–4.

215 Id. at 4. These enforcement priorities were originally outlined in the 2013 Cole Memorandum. 2013 Cole

Memorandum, supra note 182.

216 FinCEN Marijuana Guidance 2014, supra note 182, at 4–5.

217 Id. at 5–7. Some examples of red flags noted in the guidance are, “[t]he business is unable to produce satisfactory

documentation or evidence to demonstrate that it is duly licensed and operating consistently with state law”; and “[a]

customer seeks to conceal or disguise involvement in marijuana-related business activity.” Id. at 6.

218 Marijuana Banking Update, DEP’T OF TREASURY, FINCEN, https://www.fincen.gov/sites/default/files/shared/

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depository institutions are providing marijuana businesses is unclear.219 Moreover, whether these

depository institutions are serving businesses that are directly involved in cultivating and selling

marijuana, or are only serving entities that are indirectly involved in the marijuana business (e.g.,

landlords renting office space to marijuana businesses) is uncertain.220

Select Outcomes of State Marijuana Legalization

States’ actions to legalize marijuana for medical and recreational purposes changed the landscape

for the drug’s availability to the states’ adult populations. In 1996, California became the first

state to legalize marijuana for medical purposes, and since then, 36 states have followed suit.221 In

2012, Washington and Colorado became the first two states to expand access to marijuana to all

adults by legalizing its use for recreational purposes. Since then, 16 states222 and the District of

Columbia have followed suit. Even as more jurisdictions legalize marijuana, some observers

continue to voice concerns over the possible negative outcomes of legalization. Some of these

concerns were outlined as enforcement priorities by DOJ in monitoring state legalization.223

These include, but are not limited to, the potential impact of legalization on (1) marijuana use,

particularly among youth; (2) traffic-related incidents involving marijuana-impaired drivers; and

(3) trafficking of marijuana from states that have legalized it into states that have not. On the

other hand, some observers have pointed to the potential positive outcomes from marijuana

legalization, including new tax revenue for states and a potential decrease in marijuana-related

arrests, which may free up resources for law enforcement to address other needs.

While state legalization of medical marijuana began over 25 years ago, state legalization of

recreational marijuana is relatively recent and, as a result, not all outcomes are known. Further,

while some states have taken measures to evaluate the impact of their recreational legalization

programs, the same evaluation measures generally were not taken by states following medical

marijuana legalization. This section of the report focuses on select issues associated with

legalization of medical and recreational marijuana publicly identified by Congress and DOJ in

their enforcement priorities (see the “Department of Justice Guidance Memos for U.S. Attorneys”

section).224 Of note, the data included in this section of the report on the effects of marijuana

305326_MJ%20Banking%20Update%204th%20QTR%20FY2021_Public_Final.pdf (last visited March 25, 2022).

219 Robert Rowe, Compliance and the Cannabis Conundrum, ABA BANKING J. (Sept. 11, 2018),

https://bankingjournal.aba.com/2018/09/compliance-and-the-cannabis-conundrum/ (“According to FinCEN, by the end

of the third quarter 2017, it had received nearly 40,000 SARs reporting activity associated with a marijuana-related

business. The great majority of those were marijuana limited SARs, indicating that the industry continues to offer some

level of services to the cannabis industry. No one knows, though, how extensive those offerings are or what kinds of

banking relationships do exist. Anecdotal reporting suggests it is very limited.”).

220 Id.

221 See Figure 2 for all states that have adopted a comprehensive medical marijuana program.

222 The other 16 states that have legalized recreational marijuana are Alaska, Arizona, California, Connecticut, Illinois,

Maine, Massachusetts, Michigan, Montana, New Jersey, New Mexico, New York, Nevada, Oregon, Vermont, and

Virginia. In 2020, South Dakota legalized recreational marijuana, but in 2021 a circuit judge ruled the South Dakota

recreational marijuana measure to be unconstitutional.

223 See James M. Cole, Memorandum for all United States Attorneys, U.S. Department of Justice, Guidance Regarding

Marijuana Enforcement, Washington, DC, August 29, 2013, pp. 1-2.

224 See statements from U.S. Congress, House Committee on the Judiciary, Full Committee Markup of ...H.R. 3884, the

“Marijuana Opportunity Reinvestment and Expungement Act of 2019” or the “MORE Act of 2019”, 116th Cong., 1st

sess., November 20, 2019; and U.S. Congress, Senate Committee on the Judiciary, Is the Department of Justice

Adequately Protecting the Public from the Impact of State Recreational Marijuana Legalization, 114th Cong., 2nd sess.,

April 5, 2016.

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legalization should be interpreted with caution, as they are fairly limited. Conclusions made at

this time about the comprehensive impact of marijuana legalization, specifically the impact of

more recent legalization efforts, may be premature without broader inclusion of both historical

data and additional years of post-legalization data, as well as consideration of other factors aside

from legalization.225 Finally, much of what is known about the implementation of recreational

marijuana comes from the early adopters226—Washington and Colorado—and their experiences

do not necessarily mean that other states share or will share the same experiences if they choose

to legalize recreational marijuana.

Marijuana Use in the United States

Marijuana is the most commonly used illicit drug in the United States. In 2020, an estimated 32.8

million individuals aged 12 or older used marijuana in the past month.227 The percentage of pastmonth users has gradually increased over the last 12 years (a time frame during which a majority

of states legalized marijuana in some form)—from 6.1% in 2008 to 11.8% in 2020.228 The rate of

past-month marijuana use among youth (ages 12-17) during this time period declined—from

7.0% in 2008 to 6.5% in 2017 and 2018—before rising to 7.4% in 2019 and then dropping to

5.9% in 2020,229 while adult (age 18 and older) use steadily increased—from 6.3% in 2008 to

12.4% in 2020.230

An increase in adult use was expected by some experts231 given that legal medical and

recreational marijuana programs increase legal access for adults but not juveniles, except under

limited circumstances. A 2019 review of existing research on the impact of marijuana legalization

that revealed medical marijuana laws increase adult but not adolescent use is consistent with this

225 For example, in this section the decline in the number of marijuana arrests over time is discussed in the context of

marijuana legalization, but other factors such as how the overall crime rate might have changed during the same time is

not discussed. Also, drug use may be influenced by many factors including availability of the drug, family and peer

influence, level of education, economic status, and community-level variables.

226 Washington and Colorado both have produced several reports discussing the impact of marijuana legalization

following recreational legalization in their respective states. Both states had previously legalized marijuana for medical

purposes but did not produce such reports until recreational marijuana was legalized.

227 Referring to the month prior to an individual’s response to the survey question about drug use.

228 2020 NSDUH Tables, Tables 1.1A and 1.1B. For each year from 2008 to 2020, the estimated percentage of the 12

and older population currently using marijuana was 6.1%, 6.7%, 6.9%, 7.0%, 7.3%, 7.5%, 8.4%, 8.3%, 8.9%, 9.6%,

10.1%, 11.5%, and 11.8% respectively. The difference between each year’s estimate from 2008 to 2018 and the 2019

estimate (11.5%) is statistically significant at the .05 level. SAMHSA recommends using caution when comparing

estimates between 2020 and prior years because of methodological changes for 2020. Due to these changes, SAMHSA

did not conduct significance testing between 2020 and prior years.

229 For some years from 2008-2019, including the difference between the 2018 and 2019 estimate, the difference from

one year’s estimate to the next were not statistically significant at the .05 level. Further, SAMHSA recommends using

caution when comparing estimates between 2020 and prior years because of methodological changes for 2020. Due to

these changes, SAMHSA did not conduct significance testing between 2020 and prior years. See 2020 NSDUH Tables,

Table 7.6B.

230 For each year from 2008 to 2020, the estimated percentage of the adult (18 and older) population currently using

marijuana was 6.0%, 6.6%, 6.8%, 6.9%, 7.3%, 7.6%, 8.5%, 8.4%, 9.1%, 9.9%, 10.5%, 11.9%, and 12.4% respectively.

The difference between each year’s estimate from 2008 to 2018 and the 2019 estimate (11.9%) is statistically

significant at the .05 level. SAMHSA recommends using caution when comparing estimates between 2020 and prior

years because of methodological changes for 2020. Due to these changes, SAMHSA did not conduct significance

testing between 2020 and prior years. See 2020 NSDUH Tables, Table 7.9B.

231 Cari Nierenberg, “Marijuana’s Popularity Among US Adults Continues to Grow. Here’s Why,” Live Science,

August 10, 2017.

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view.232 Further, several studies have either concluded that state medical and recreational

marijuana laws have had no effect on youth use or have shown an association between the

enactment of these laws and a subsequent decline in youth use.233 Two studies have indicated that

adolescent use may decline after state recreational legalization.234 Other studies have shown youth

and/or adolescent use did not increase in states following recreational and medical marijuana

legalization and that youth and/or adolescent marijuana use were already elevated in these states

prior to legalization.235

Monitoring Use and Health Effects

Some states that have legalized marijuana are monitoring changes in drug use patterns in their states as well as

changes in the emerging research on the health effects of marijuana. For example, new studies of marijuana’s effect

on brain functioning and development are often published in medical journals. Some have pointed to a negative

effect on brain development while others point to an effect that is not necessarily positive or negative. 236 For

more information on the health effects of marijuana use, see Appendix B and Appendix C.

A concern of policymakers is that youth perception of the harmfulness of marijuana may be lower

in states that allow for either or both medical and recreational marijuana. Perceived harmfulness

of marijuana use appears to be

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