# Enforcement of Federal Pollution Control Laws

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URL: https://www.frixlaw.com/law-library/documents/crs%3AR48926

## Record

- **Collection:** Congressional research report
- **Document type:** Reports
- **Published:** April 27, 2026
- **Citation:** R48926

## Text

Enforcement of Federal Pollution Control
Laws
April 27, 2026

Congressional Research Service
https://crsreports.congress.gov
R48926

SUMMARY

Enforcement of Federal Pollution Control Laws
Congress has enacted an array of statutes designed to protect the environment and human health
from the impacts of pollution. These laws allow the government, and sometimes private parties,
to pursue enforcement actions against those who violate statutory requirements or prohibitions.
Whether and how the statutes are enforced informs how well they achieve Congress’s legislative
goals. Federal pollution control statutes generally require regulated entities to apply for, obtain,
and abide by permits to conduct certain activities involving potential discharges of pollutants to
the environment. These laws also typically have robust recordkeeping and reporting
requirements, which facilitate government oversight. The U.S. Environmental Protection Agency
(EPA) monitors compliance pursuant to its civil inspection and criminal investigation authorities.

R48926
April 27, 2026
Cassandra J. Barnum
Legislative Attorney
Kate R. Bowers
Supervisory Attorney
Andrew S. Coghlan
Legislative Attorney

EPA and the U.S. Department of Justice (DOJ) typically conduct enforcement actions on behalf
of the federal government. Many statutes also authorize “citizen suits”—lawsuits by nonfederal
actors seeking injunctive relief or penalties with respect to alleged violations. Enforcement
actions generally fall into one of three broad categories: administrative enforcement, civil judicial
enforcement, and criminal enforcement.
Administrative enforcement refers to actions taken by EPA outside the court system. Such actions can include orders to take
corrective action, withdrawal of permits, and imposition of penalties up to certain amounts. These actions require various
degrees of process; some corrective action orders can be issued based on an agency determination that a violation has
occurred, while permit withdrawals or money penalties typically follow a hearing where the accused has an opportunity to
submit evidence to a neutral adjudicator. Administrative enforcement actions are subject to judicial review, allowing courts to
determine whether agencies have acted within the scope of their statutory and constitutional authority. Exercising that power
of review, the Supreme Court recently held that administrative hearings may violate the Seventh Amendment right to trial by
jury, though the effect of that ruling on EPA’s administrative enforcement actions remains unsettled.
Civil judicial enforcement refers to lawsuits against alleged violators filed in federal court by the federal government or by
nonfederal actors, including state and local governments, private citizens, and advocacy groups. Plaintiffs must prove
violations by a preponderance of the evidence, and consequences can include both monetary penalties and injunctive relief
(often involving cleanup of polluted sites or actions to assure prospective compliance). Settlements of civil judicial actions
can be private, out-of-court agreements or can be formalized in a consent decree enforceable by a court. Civil judicial
enforcement cases initiated by nonfederal actors implicate an additional suite of legal considerations that arise under Article
III of the Constitution, which limits federal court jurisdiction to cases or controversies. Unlike the federal government, citizen
suit plaintiffs must demonstrate their “standing” to bring suit by showing that they have suffered a concrete and particularized
injury in fact that is fairly traceable to the alleged violation and redressable by available remedies.
Criminal prosecution is generally reserved for violations committed with a particular degree of intent, or mens rea. Various
environmental statutes criminalize violations committed negligently, knowingly, or willfully. Environmental laws prohibiting
“knowing violation” of a permit or regulatory requirement have led courts to consider whether defendants must be aware
only of their actions or also that their actions violate such requirements. The answer sometimes depends on the subject matter
of the law; courts have found that certain “public welfare offenses” involving hazardous devices or substances can require a
reduced showing of knowledge without offending due process, but courts have disagreed about whether the various
environmental laws fall within this category. Corporations may be liable for environmental crimes based on the actions of
their employees, and certain “responsible corporate officers” may be prosecuted for actions taken by subordinates. Applicable
criminal penalties include jail time, criminal fines, and special conditions of probation.
The executive branch enjoys broad discretion in its enforcement of environmental laws, subject to certain constitutional
constraints. Various policies govern EPA’s and DOJ’s exercise of that enforcement discretion, many of which vary widely
across presidential administrations. Supplemental environmental projects, in which a judicial settlement involves a
commitment to undertake a project benefiting the environment, have been a particular source of controversy in recent years.
To alter the terms of environmental enforcement, Congress may amend underlying statutes to redefine violations, change
who may enforce a statute, or change the penalties and remedies that may be imposed for statutory violations. Congress also
may use its appropriations power to increase or decrease funding for enforcement activities or conduct oversight on changing
enforcement policies and priorities across administrations.

Congressional Research Service

Enforcement of Federal Pollution Control Laws

Contents
Introduction ..................................................................................................................................... 1
Identifying Violations ...................................................................................................................... 4
Types of Federal Enforcement ......................................................................................................... 4
Administrative Enforcement ..................................................................................................... 5
Types of Administrative Enforcement Action ..................................................................... 5
Administrative Enforcement Procedures ............................................................................ 6
Review of Administrative Enforcement Actions ................................................................ 9
Administrative Enforcement and the Seventh Amendment ...............................................11
Civil Judicial Enforcement ...................................................................................................... 13
DOJ’s Role ........................................................................................................................ 14
Legal Standard, Burden of Proof, and Statute of Limitations ........................................... 15
Available Remedies .......................................................................................................... 15
Settlement Agreements and Consent Decrees ................................................................... 17
Citizen Suits ...................................................................................................................... 19
Criminal Enforcement ............................................................................................................. 24
Types of Criminal Provisions in Environmental Laws ..................................................... 25
Title 18 Criminal Offenses ................................................................................................ 26
The Mens Rea Requirement .............................................................................................. 27
Responsible Corporate Officers ........................................................................................ 34
Penalties ............................................................................................................................ 36
Enforcement Discretion and Agency Policy .................................................................................. 39
Enforcement Discretion, Generally ......................................................................................... 40
Limits on Enforcement Discretion .................................................................................... 40
Programmatic Nonenforcement ........................................................................................ 42
Enforcement Policies .............................................................................................................. 43
Strategic Enforcement Priorities ....................................................................................... 44
Supplemental Environmental Projects .............................................................................. 45
Considerations for Congress.......................................................................................................... 47
Changing Enforcement Policies and Priorities ........................................................................ 48
Enforcement by States and Citizens ........................................................................................ 49
Setting Penalties and Defining Remedies ............................................................................... 50
Responding to SEC v. Jarkesy ................................................................................................. 51

Tables
Table A-1. Selected Civil Penalty Provisions in Federal Pollution Control Laws ........................ 53
Table A-2. Selected Citizen Suit Provisions in Federal Pollution Control Laws .......................... 56
Table A-3. Selected Criminal Provisions of Federal Pollution Control Laws ............................... 59

Appendixes
Appendix. Selected Enforcement Provisions ................................................................................ 52

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Contacts
Author Information........................................................................................................................ 62

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Introduction
Congress has enacted a number of statutes designed to safeguard the environment and human
health by maintaining the integrity of the nation’s land, air, and water. Whether Congress’s goals
for these laws are met depends in part on how the laws are enforced. Generally speaking, these
statutes, referred to herein as “federal pollution control statutes,” prohibit certain types of releases
of pollutants into the environment unless authorized by a permit.1 Such permitting regimes can
apply to various industrial, commercial, and personal activities that risk contaminating the
environment or endangering human health. Discharge of wastewater from industrial activity,
emission of airborne substances from smokestacks, and disposal of hazardous waste are just three
examples of regulated activity that generally can be undertaken only pursuant to a permit issued
under the relevant statutory authority.2 Conducting such prohibited activities without a permit or
in violation of the terms of a permit can give rise to a variety of enforcement actions under federal
pollution control laws. Those laws typically provide that enforcement can be against “any person”
in violation of the statute, where “person” is generally defined to include individuals,
corporations, state and local governments, and the federal government.3 The government or, in
some cases, private citizens can undertake enforcement.4 On the federal level, the U.S.
Environmental Protection Agency (EPA) enforces most of the pollution control statutes, either
alone or in conjunction with the U.S. Department of Justice (DOJ).5
This report provides an overview of what such enforcement entails. It begins with a brief
discussion of how the government uncovers and investigates environmental violations. A
fundamental difficulty for environmental enforcement is that environmental harm can be diffuse,
hard to detect, and harder still to trace back to a single source. Given these challenges, many
environmental laws require the regulated community to self-identify, obtain permits to operate,
and monitor their own operations for compliance with statutory, regulatory, or permit
requirements.6 Agency reviews of required reports, civil inspections, and criminal investigations
complement this self-policing regime.7 In light of the critical role self-reporting plays in these
regulatory regimes, several statutes have penalty provisions specifically targeting failure to
maintain required records or falsifying reports.8

1 See, e.g., Clean Water Act, 33 U.S.C. §§ 1251–1387; Clean Air Act, 42 U.S.C. §§ 7401–7671q. The various

enforcement provisions of laws addressed in this report are listed in Tables A1–A3, infra.
2 Id.; see also Resource Conservation and Recovery Act, 42 U.S.C. §§ 6901–6992. To varying degrees, jurisdictional
limitations within the federal pollution control statutes mean that not all such polluting activities implicate federal
statutory requirements. For example, the Clean Water Act prohibits certain discharges only to “waters of the United
States” and certain publicly owned treatments works. See 33 U.S.C. § 1319. Discharges to other water bodies may
nonetheless be subject to state or local regulation.
3 See, e.g., 33 U.S.C. § 1362(5). The federal government is typically a defendant in civil suits only when sued by a
private citizen, because the government generally cannot criminally prosecute or sue itself; certain administrative
remedies may nonetheless be available. See infra notes 47–48 and accompanying text; see also infra notes 137–139 and
accompanying text.
4 See “Citizen Suits,” infra.
5 Certain statutes addressed herein are enforced by other agencies—often but not always in conjunction with EPA—
such as the U.S. Coast Guard, for the Act to Prevent Pollution from Ships; the U.S. Department of Transportation and
Federal Aviation Administration (FAA), for the Hazardous Materials Transportation Act; or the U.S. Army Corps of
Engineers, for certain parts of the Clean Water Act.
6 See David M. Uhlmann, Prosecutorial Discretion and Environmental Crime, 38 HARV. ENV’T L. REV. 159, 197–98
(2014).
7 See “Identifying Violations,” infra.
8 See, e.g., 33 U.S.C. § 1319(c)(4); 42 U.S.C. § 6928(d)(3).
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Selected Pollution Control Law Names and Acronyms9
Act to Prevent Pollution from Ships (APPS)
Clean Air Act (CAA)
Clean Water Act (CWA)
Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA)
Emergency Planning and Community Right-to-Know Act (EPCRA)
Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA)
Hazardous Materials Transportation Act (HMTA)
Marine Protection, Research, and Sanctuaries Act (MPRSA)
Resource Conservation and Recovery Act (RCRA)
Safe Drinking Water Act (SDWA)
Toxic Substances Control Act (TSCA)

This report then addresses the legal enforcement mechanisms available under the federal
pollution control statutes: administrative actions, civil judicial suits by the government and by
private citizens, and criminal prosecutions.
•

•

•

Administrative enforcement refers to actions agencies take without going
through the courts, which can result in penalties, permit withdrawals, or orders to
do (or not do) certain things.10
Civil judicial enforcement refers to DOJ filing lawsuits in federal court by DOJ
on behalf of EPA to enforce statutory prohibitions or requirements or to compel
compliance with administrative orders; such lawsuits can result in financial
penalties or injunctive relief.11 The federal government may pursue civil judicial
enforcement actions under all the pollution control statutes, and several such laws
also allow private citizens to initiate civil judicial enforcement actions.12
Criminal enforcement is available under most pollution control statutes when
offenses are committed with a certain degree of intent, exposing violators to
criminal prosecution, fines, and potential prison time.13 While administrative and
civil judicial enforcement generally can result from unwitting conduct or
accidents, essentially resulting in a strict-liability regime,14 criminal penalties
typically apply in cases where violations are committed with a specific mental
state.15

Next, this report discusses the enforcement discretion that executive branch officials wield when
undertaking enforcement action and the policies that EPA and DOJ have adopted to guide the
9 This list, presented in alphabetical order, includes statutes referenced in this report and does not encompass every

potential federal statute governing pollution.
10 See “Administrative Enforcement,” infra.
11 See “Civil Judicial Enforcement,” infra.
12 Id.
13 See “Criminal Enforcement,” infra.
14 Pollution control laws typically define violations, and establish civil liability, without regard to the violator’s mental
state. See, e.g., 7 U.S.C. §§ 136a, 136l (FIFRA); 15 U.S.C. §§ 2614, 2615(a)(1), 2689 (TSCA); 33 U.S.C. § 300h-2(a)–
(c) (SDWA); id. §§ 1311(a), 1319(a)–(b) (CWA); id. §§ 1411(a)–(b), 1415(a) (MPRSA); 42 U.S.C. § 7413(a)–(b)
(CAA); id. § 6928(a)(3), (g), (h)(2) (RCRA); id. § 11045(b)(1)–(3) (EPCRA); see also Burlington N. & Santa Fe Ry.
Co. v. United States, 556 U.S. 599, 608 (2009) (noting that “CERCLA imposes strict liability for environmental
contamination”).
15 See “The Mens Rea Requirement,” infra.
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exercise of that discretion. While Congress enacts the laws governing pollution control, the
executive branch typically enjoys broad discretion with respect to when and how those laws are
enforced.16 Limited resources may preclude universal enforcement, and both the executive branch
and Congress, via its appropriations power, have a role to play in targeting enforcement efforts.17
The report concludes with several considerations for Congress, including options to address
changing executive branch enforcement policies and priorities, the role of enforcement by
nonfederal actors, the scope of available remedies and penalties, and the availability of
administrative enforcement in light of recent Supreme Court jurisprudence.
The pollution control statutes discussed in this report are a subset of the broader class of federal
environmental laws, which include wildlife protection measures such as the Endangered Species
Act,18 natural resource and land-use measures such as the Outer Continental Shelf Lands Act,19
and procedural measures such as the National Environmental Policy Act.20 This report focuses on
the pollution statutes listed in Table A-1, Table A-2, and Table A-3 as a framework for
discussion, but many of the issues discussed herein may be applicable to the wider canon of
federal environmental law.
Many pollution control laws authorize states to implement national standards pursuant to an EPAapproved state-law program that satisfy certain minimum federal requirements. Under this
“cooperative federalism” approach,21 state environmental protection agencies often take the lead
in issuing permits under federal pollution statutes, conducting inspections, and pursuing certain
enforcement measures under federal and state law.22 These pollution control statutes afford states
significant discretion in choosing how to structure and implement their programs, which can vary
considerably. While state agencies can play an important role in certain states’ enforcement
schemes, this report is limited in scope to enforcement of federal pollution control laws by the
federal government or through citizen suits in federal court.
This report also focuses on affirmative enforcement actions taken in response to alleged
violations of statutory or regulatory prohibitions or requirements. Some claims brought by private
individuals in citizen suits may allege that EPA is failing to perform a statutorily mandated duty.
Although this type of claim could fairly be characterized as a type of “enforcement,” such
lawsuits raise a unique set of legal considerations and are beyond the scope of this report.
Likewise, this report does not address remedial provisions of the Comprehensive Environmental
Response, Compensation, and Liability Act (CERCLA) that apportion cleanup costs through a
no-fault liability scheme but do not proscribe conduct.23

16 See infra.
17 Id.
18 16 U.S.C. §§ 1531–1544.
19 43 U.S.C. §§ 1331–1356.
20 42 U.S.C. §§ 4321–4347.
21 See CRS Legal Sidebar LSB11309, Cooperative Federalism and the Clean Air Act: EPA’s Good Neighbor Interstate

Air Pollution Rule, by Kate R. Bowers (2025) (describing role of cooperative federalism in environmental law).
22 See Memorandum from Lawrence E. Starfield, Acting Assistant Adm’r, Off. of Enf’t and Compliance Assurance
(OECA), EPA, to Reg’l Adm’rs et al., Effective Partnerships Between EPA and the States in Civil Enforcement and
Compliance Assurance 1 (June 21, 2023), https://www.epa.gov/system/files/documents/202306/effectivepartnershipsbetweenepaandthestatesincivilenforcementandcomplianceassurance062123.pdf
[https://perma.cc/GKV4-GTU2].
23 For an overview of CERCLA’s remedial liability scheme, see CRS In Focus IF11790, Liability Under the
Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), by Kate R. Bowers (2021).
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Identifying Violations
Enforcement begins with identifying violations, which can consist of unpermitted or otherwise
illegal pollution activity, pollution activity in violation of a permit, and recordkeeping violations,
among other things. EPA compliance-monitoring activity includes on-site inspections and off-site
review of data.24 Civil inspections consist of site visits to evaluate compliance by means of
observation, document review, interviews, and/or sampling activity.25 Inspection results, record
reviews, or civilian complaints indicating “serious, widespread, and/or continuing civil
violations” may trigger more in-depth civil investigations that can include enforceable written
information requests.26
EPA also has a Criminal Investigation Division, whose law enforcement officers are authorized
under federal law to carry firearms, serve and execute search and seizure warrants and other
forms of legal process, and make arrests.27 In conjunction with DOJ, any suspected criminal
violation can be opened as a matter before a federal grand jury, authorizing issuance of subpoenas
to compel documents and testimony.28
EPA can also learn of violations by way of tips, whether from whistleblower employees or from
the public.29 Certain statutes allow for awards up to a maximum dollar amount to tipsters whose
information results in successful enforcement actions,30 while the Act to Prevent Pollution from
Ships allows courts, in their discretion, to award whistleblowers up to half the amount of any civil
or criminal penalty imposed as a result of their information.31
EPA’s audit policy establishes conditions under which voluntary self-disclosure of violations can
result in civil penalty mitigation or a determination not to pursue a criminal case.32

Types of Federal Enforcement
Federal environmental enforcement falls into three broad categories: administrative enforcement,
civil judicial enforcement, and criminal enforcement.

24 Monitoring Compliance, EPA (Mar. 17, 2026), https://www.epa.gov/compliance/monitoring-compliance

[https://perma.cc/4PNE-YGH7].
25
Id.
26 Id.
27 See 18 U.S.C. § 3063.
28 See FED. R. CRIM. P. 6, 17.
29 See EPA, Report Environmental Violations, ENF’T & COMPLIANCE HIST. ONLINE, https://echo.epa.gov/reportenvironmental-violations [https://perma.cc/5UNF-869X] (last visited Apr. 27, 2026).
30 See, e.g., 42 U.S.C. § 7413(f) (CAA) (“The Administrator may pay an award, not to exceed $10,000, to any person
who furnishes information or services which lead to a criminal conviction or a judicial or administrative civil penalty
for any violation . . . under this section.”); 42 U.S.C. § 9609(d) (CERCLA) (authorizing $10,000 award to “any
individual who provides information leading to the arrest and conviction of any person for a violation subject to a
criminal penalty under this chapter”).
31 See 33 U.S.C. § 1908(a) (“In the discretion of the Court, an amount equal to not more than ½ of such fine may be
paid to the person giving information leading to conviction.”); see also id. § 1908(b)(2) (enforcing agencies may award
up to half of civil penalties to person giving information leading to penalty assessments).
32 See EPA’s Audit Policy, EPA (Oct. 8, 2025), https://www.epa.gov/compliance/epas-audit-policy
[https://perma.cc/WLP5-UTFP].
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Administrative Enforcement
In administrative enforcement actions, agencies exercise statutory authority to determine whether
violations have occurred and what statutorily authorized administrative remedies are appropriate
to address those violations. Agencies typically make these determinations using procedures that
are simpler and faster than civil litigation in federal court.33 By case volume, the vast majority of
EPA’s civil enforcement activity is administrative: the agency initiates more than 10 new
administrative enforcement actions for every new civil judicial enforcement action.34
EPA decides whether and how to exercise its administrative enforcement authority, but those it
targets can seek judicial review.35 Courts thus ensure that EPA acts within the bounds of its
statutory and constitutional authority. Courts also play an essential role in enforcing compliance
with EPA’s administrative directives: While EPA can issue administrative orders or assess
penalties, the agency’s main recourse against noncompliant entities is to bring suit.36

Types of Administrative Enforcement Action
Pollution control statutes authorize EPA to pursue three administrative enforcement responses to
suspected violations.
First, most statutes allow EPA to issue administrative compliance orders that direct entities to take
corrective actions necessary to cure alleged violations and remedy environmental harms, usually
within a specified time frame.37 This authority is often, though not always, predicated on a
finding that the violation in question poses an “imminent and substantial endangerment” to public
health or the environment.38 If a party fails to comply with EPA’s administrative orders, it may be
liable for civil penalties in a subsequent administrative or civil judicial enforcement action.39

33 See Todd S. Aagard, Agencies, Courts, First Principles, and the Rule of Law, 70 ADMIN. L. REV. 771, 786 (2018)

(noting that “agencies are able to create processes that, through specialization and routinization, make decisions with
greater speed and at lower cost than courts do”).
34 See EPA, ENFORCEMENT AND COMPLIANCE ASSURANCE ANNUAL RESULTS FOR FISCAL YEAR 2024, at 168 (2024),
https://www.epa.gov/system/files/documents/2025-03/eoy2024.pdf [https://perma.cc/CKC4-3S9W] (noting 60 new
complaints in civil judicial enforcement actions, as compared with new 987 complaints seeking administrative
penalties); EPA, ENFORCEMENT AND COMPLIANCE ASSURANCE ANNUAL RESULTS FOR FISCAL YEAR 2023, at 106 (2023),
https://www.epa.gov/system/files/documents/2025-03/eoy2023.pdf [https://perma.cc/32TS-SFSP] (noting 79 new
complaints in civil judicial enforcement actions, as compared with 912 complaints seeking administrative penalties).
Some commentators have observed that the ratio of administrative to civil judicial enforcement actions has grown
substantially in the first year of the second Trump Administration, though EPA’s most recent annual report does not
include comparative data on newly filed actions. See ENV’T INTEGRITY PROJECT, DECLINING ENVIRONMENTAL
ENFORCEMENT IN TRUMP’S SECOND TERM (2026), https://environmentalintegrity.org/wp-content/uploads/2026/02/
EIP_Report_2025EnvironmentalEnforcement_2.5.26.pdf [https://perma.cc/SHV5-9UHB].
35 See “Civil Judicial Enforcement,” infra.
36 Id.
37 See, e.g., 7 U.S.C. § 136k(a) (FIFRA); 33 U.S.C. § 1319(a)(3) (CWA); 42 U.S.C. § 6928(a)(1) (RCRA); id.
§ 7413(a)(1) (CAA), id. § 9606(a) (CERCLA), id. § 11045(a) (EPCRA).
38 See, e.g., 42 U.S.C. § 9606(a) (authorizing “such orders as may be necessary to protect public health and welfare and
the environment” when “an actual or threatened release of a hazardous substance” poses an “imminent and substantial
endangerment”); id. § 6973 (authorizing similar orders to respond to an “imminent and substantial endangerment”
related to solid or hazardous waste); id. § 7603 (authorizing similar orders to respond to an imminent and substantial
endangerment related to air pollution); id. § 300i(a) (authorizing similar orders to respond to an “imminent and
substantial endangerment” related to a contaminant that “is present in or is likely to enter a public water system”).
39 See infra notes 41 and 129 and accompanying text.
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Second, some statutes authorize EPA to withdraw certain permits from noncompliant
permittees.40
Third, most statutes authorize EPA to order payment of administrative penalties to punish and
deter noncompliance, including, in some cases, noncompliance with EPA’s own administrative
compliance orders.41 These statutes set maximum penalty amounts, which are adjusted for
inflation (see Table A-1).42 Current maximum penalties vary across statutes, but most are
between $20,000 and $70,000 per violation.43 EPA does not have to seek maximum penalties,
however, and many statutes identify factors that EPA must consider when determining
appropriate penalties in a given case.44 These statutory penalty factors may include, for example,
“the nature, circumstances, extent and gravity of the violation, or violations, and, with respect to
the violator, ability to pay, any prior history of such violations, the degree of culpability, and
economic benefit or savings (if any) resulting from the violation.”45 Statutory penalties are often
assessed for each day that a violation persists, but some statutes cap the aggregate penalties that
EPA can collect through administrative action and require the agency to bring a civil judicial
action to seek penalties that exceed those caps.46
The federal government is generally subject to requirements under pollution control statutes, and
EPA has statutory authority to issue administrative orders and assess administrative penalties
against federal facilities that violate the CAA, RCRA, and SDWA.47 EPA lacks that authority
under the CWA, TSCA, FIFRA, and EPCRA.48

Administrative Enforcement Procedures
The procedures that EPA must follow when bringing an administrative enforcement action
generally depend on the administrative remedy that the agency pursues. For instance, several
statutes authorize EPA to issue administrative compliance orders without first obtaining
information from violators or the public, or proving to a neutral adjudicator that a violation has
occurred. To illustrate, the CWA and CAA both authorize EPA to issue orders if the agency
believes, based on “any information available to” the Administrator, that a violation has

40 E.g., 33 U.S.C. § 1415(f); 42 U.S.C. § 6928(a)(3).
41 See, e.g., 7 U.S.C. § 136l(a)(1) (FIFRA); 15 U.S.C. §§ 2615(a)(2)(A), 2647(a) (TSCA); 33 U.S.C. §§ 1319(g)(2)(A)–

(B), 1321(b)(6)(B)(i)–(ii) (CWA); 42 U.S.C. §§ 6928(a)(3), 6928(c), 6928(h)(2) (RCRA); id. §§ 7413(d)(1), 7524(c)(1)
(CAA); id. § 9609(a) (CERCLA); id. § 11045(b)(1)–(2) (EPCRA).
42 Federal Civil Penalties Inflation Adjustment Act of 1990, Pub. L. No. 114-74, § 5, 104 Stat. 890, 891–92 (codified as
amended at 28 U.S.C. § 2461 note).
43 40 C.F.R. § 19.4, tbl. 1 (2025).
44 E.g., 15 U.S.C. § 2615(a)(2)(A)–(B); 33 U.S.C. § 1319(g)(3); 42 U.S.C. §§ 7413(e), 9609(a)(3).
45 33 U.S.C. § 1319(g)(3).
46 See e.g., 33 U.S.C. § 1319(g)(1)–(2) (capping CWA administrative penalties); 42 U.S.C. § 300h-2(c)(1)–(2) (capping
SDWA administrative penalties); cf. 42 U.S.C. § 7413(d)(1) (capping CAA administrative penalties at $200,000, unless
“the Administrator and the Attorney General jointly determine that a matter involving a larger penalty amount . . . is
appropriate for administrative penalty action”); accord id. § 7524(c)(1).
47 Overview of the Enforcement Process for Federal Facilities, EPA, (May 6, 2025),
https://www.epa.gov/enforcement/overview-enforcement-process-federal-facilities [https://perma.cc/4C9Q-Y6DQ].
48 Id.
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occurred.49 Similarly, RCRA authorizes EPA to issue orders if the Administrator “has reason to
believe” that violations have occurred.50
By contrast, when statutes authorize EPA to withdraw permits or order payment of monetary
penalties, they typically require the agency to provide an opportunity for the accused to submit
evidence at a hearing.51 Some of these statutes also require EPA to conduct its hearings in
accordance with the Administrative Procedure Act’s (APA’s) rules for “formal adjudications.”52
Those rules require trial-like adversarial proceedings before agency heads or administrative law
judges (ALJs), who weigh evidence, determine whether a violation occurred, and decide what
remedy is warranted53—powers that the Supreme Court has described as “functionally
comparable” to those exercised by Article III judges presiding over bench trials.54
EPA’s hearings are governed by the agency’s Consolidated Rules of Practice, which are codified
at 40 C.F.R. Part 22.55 These regulations establish procedures for the presentation of evidence,
including the examination and cross-examination of witnesses.56 They also designate ALJs as
presiding officers for hearings that are subject to the APA’s “formal adjudication” procedures and
regional judicial officers (RJOs) as the presiding officers for hearings that are not subject to those
procedures.57 RJOs and ALJs perform similar functions, but ALJs are subject to several APAmandated limits designed to ensure their impartiality.58 For instance, unlike RJOs,59 ALJs cannot
49 33 U.S.C. § 1319(a)(3); 42 U.S.C. § 7413(a)(1); see also Tenn. Valley Auth. v. Whitman, 336 F.3d 1236, 1241 (11th

Cir. 2003) (holding that the CAA’s “language and structure, in addition to agency practice, make clear that [compliance
orders under the CAA] are issued without any adjudication”).
50 7 U.S.C. § 136k; see also 42 U.S.C. §§ 6928(a)(1), 11045(a) (authorizing issuance of administrative orders without a
hearing under RCRA and EPCRA, respectively). But see 42 U.S.C. § 6991e (requiring EPA to provide an opportunity
for a hearing before issuing a compliance order addressing violations of RCRA’s requirements for underground storage
tanks); id. § 9613(k)(2)(B) (requiring EPA, as the President’s designee, to seek public comment before ordering a
remedial action under CERCLA to address releases of hazardous waste).
51 E.g., 7 U.S.C. 136l(a)(3); 33 U.S.C. §§ 1319(g)(2)(A), 1321(b)(6)(B)(i), 1415(a), (f); 42 U.S.C. §§ 300g-3(g)(B),
300h-2(c)(3). But see 42 U.S.C. § 6925(d) (authorizing EPA to revoke certain permits under RCRA without holding a
hearing).
52 E.g., 15 U.S.C. § 2615(a)(2)(A); 33 U.S.C. §§ 1319(g)(2)(B), 1321(b)(6)(B)(ii), 42 U.S.C. §§ 300j-6(b)(3), 6928(b),
7413(d)(2), 7524(c)(1), 9609(a)(2), (5), 11045(b)(2), 14304(e). The APA establishes baseline procedural requirements
that federal agencies must follow when taking various actions, including adjudication. 5 U.S.C. §§ 551(6)–(7), 554,
556–57. See also CRS Report R46930, Informal Administrative Adjudication: An Overview, by Ben Harrington and
Daniel J. Sheffner (2021).
53 5 U.S.C. §§ 556(b)–(c), 557(b).
54 Butz v. Economou, 438 U.S. 478, 481–82 (1978).
55 For summaries and interpretations of the Consolidated Rules of Practice, see EPA, GUIDE TO THE U.S.
ENVIRONMENTAL PROTECTION AGENCY’S ENVIRONMENTAL APPEALS BOARD (2025), https://www.epa.gov/system/files/
documents/2026-01/guide-to-the-eab-2025.pdf [https://perma.cc/C7EZ-JMHM] [hereinafter EAB GUIDE]; Joseph F.
Guida & Jean M. Flores, From Here to a Penalty: Anatomy of EPA Civil Administrative Enforcement, 43 TEX. ENV’T.
L.J. 129 (2013); Joseph J. Lisa, EPA Administrative Enforcement Actions: An Introduction to the Consolidated Rules of
Practice, 24 TEMP. J. SCI. TECH. & ENV’T. L. 1 (2005).
56 40 C.F.R. pt. 22, subpt. D.
57 40 C.F.R. §§ 22.3; 22.19; 22.22–22.24; see also EPA, Regional Judicial Officers, EPA ADMIN. ENFORCEMENT
DOCKETS (Apr. 17, 2026), https://yosemite.epa.gov/oa/rhc/epaadmin.nsf/e2d1f35fbb02bc3f8525753f006961b0/
7c1126a0949e9ab28525764f006dbae4!OpenDocument [https://perma.cc/LCM5-GBWL] (discussing the roles of ALJs
and RJOs under the Consolidated Rules of Practice).
58 5 U.S.C. §§ 554(d)(1)–(2), 557(d), 7521; see also Ramspeck v. Fed. Trial Exam’rs Conf., 345 U.S. 128, 130 (1953)
(discussing the APA’s legislative history and describing the statute’s protections for ALJs as a congressional response
to “complaint[s]” that early New Deal hearing examiners “were mere tools of the agency concerned and subservient to
the agency heads in making their proposed findings of fact and recommendations”).
59 KENT BARNETT ET AL., ADMIN. CONF. OF THE U.S., NON-ALJ ADJUDICATORS IN FEDERAL AGENCIES: STATUS,
(continued...)
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perform investigative or prosecutorial functions, cannot report to an employee who does,60 and
can be removed from their role “only for good cause established and determined by the Merit
Systems Protection Board on the record after opportunity for hearing before the Board.”61
Under the Consolidated Rules of Practice, EPA must establish liability by a “preponderance of the
evidence,” the “most common” burden of proof “in the civil law.”62 To carry that burden in an
administrative hearing, EPA must persuade the presiding ALJ or RJO “that a proposition is more
likely true than not true.”63
At least one pollution control law limits the time in which EPA can bring an administrative
enforcement action,64 but absent such a statute-specific limitation period, EPA’s authority to seek
administrative penalties is subject to the general statute of limitations codified at 28 U.S.C.
§ 2462.65 Under that law, “an action, suit or proceeding for the enforcement of any civil fine,
penalty, or forfeiture, pecuniary or otherwise, shall not be entertained unless commenced within
five years from the date when the claim first accrued.”66
In the environmental enforcement context, courts have held that a claim accrues at the time of the
violation, not when the government learns of that violation.67 The impact of this timing rule
depends, in part, on the nature of the violation at issue. Congress has defined some violations—
illegal ocean dumping, for example—to recur each day that the violation persists.68 For these
types of “continuing” violations, EPA can seek administrative penalties based on any conduct that
occurred within the past five years, even if the violative conduct began more than five years
ago.69 Conversely, courts have held that other violations—the failure to obtain a required CAA
SELECTION, OVERSIGHT, AND REMOVAL 1, 45–46 (2018), https://www.acus.gov/document/non-alj-adjudicators-federalagencies-status-selection-oversight-and-removal-final-report [https://perma.cc/VA6A-5972?type=image].
60 5 U.S.C. § 554(d)(1)–(2).
61 5 U.S.C. § 7521. The APA’s tenure protections for ALJs have been the subject of judicial scrutiny and courts are
divided on whether those protections are constitutional. Compare Decker Coal Co. v. Pehringer, 8 F.4th 1123, 1133–35
(9th Cir. 2021), Rabadi v. DEA, 122 F.4th 371, 374–77 (9th Cir. 2024), cert. denied, 145 S. Ct. 2846 (2025), Leachco,
Inc. v. Consumer Prod. Safety Comm’n, 103 F.4th 748, 764 (10th Cir. 2024), cert. denied, 145 S. Ct. 1047 (2025), and
Walmart, Inc. v. Chief Admin. L. Judge of Off. of Chief Admin. Hearing Officer, 144 F.4th 1315, 1342–48 (11th Cir.
2025) (holding that removal protections are constitutional), with Jarkesy v. SEC, 34 F.4th 446, 464 (5th Cir. 2022),
aff’d on other grounds and remanded, 603 U.S. 109 (2024), and VHS Acquisition Subsidiary No. 7 v. NLRB., 759 F.
Supp. 3d 88, 92–100 (D.D.C. 2024) (holding that removal protections are unconstitutional).
62 Concrete Pipe & Prods. of Cal., Inc. v. Constr. Laborers Pension Tr. for S. Cal., 508 U.S. 602, 622 (1993).
63 United States v. Watkins, 10 F.4th 1179, 1185 (11th Cir. 2021) (quoting United States v. Deleveaux, 205 F.3d 1292,
1296 n.3 (11th Cir. 2000)).
64 42 U.S.C. § 7413(d)(1) (limiting EPA’s administrative penalty authority under the CAA to actions where “the first
alleged date of violation occurred no more than 12 months prior to the initiation of the administrative action, except
where the Administrator and the Attorney General jointly determine that a matter involving a . . . longer period of
violation is appropriate for administrative penalty action”).
65 See 3M Co. v. Browner, 17 F.3d 1453, 1457 (D.C. Cir. 1994) (holding that an administrative action seeking penalties
is “an action, suit or proceeding” subject to 28 U.S.C. § 2462’s five-year limitations period).
66 28 U.S.C. § 2462. The same statute of limitations governs the civil judicial enforcement actions discussed later in
this report. See Coghlan v. Nat’l Transp. Safety Bd., 470 F.3d 1300, 1305 (11th Cir. 2006) (“Section 2462 encompasses
not only judicial proceedings, but also administrative proceedings that fall within the scope of its language.”).
67 E.g., 3M Co., 17 F.3d at 1460–63; accord United States v. Core Lab’ies, Inc., 759 F.2d 480, 482–84 (5th Cir. 1985);
see also Gabelli v. SEC, 568 U.S. 442, 447–48 (2013) (The “‘standard rule’ is that a claim accrues” under 28 U.S.C.
§ 2462 “when the plaintiff has a complete and present cause of action.” (quoting Wallace v. Kato, 549 U.S. 384, 388
(2007))).
68 33 U.S.C. §§ 1415(c), 1908(b).
69 See United States v. Midwest Generation, LLC, 720 F.3d 644, 647 (7th Cir. 2013) (noting that “Congress sometimes
writes regulatory statutes” so “that every day” of violation “is a fresh violation” of the statute).
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construction permit, for example—occur at a discrete point in time.70 Even if these violations are
never corrected, EPA must act within five years of the date of violation if it wants to secure
administrative penalties.71
Because 28 U.S.C. § 2462’s general limitations period applies only to actions seeking “fine[s],
penalt[ies], or forfeiture[s],” it does not limit injunctive remedies that require parties to take or
refrain from taking certain actions but that entail no monetary penalty or asset forfeiture and are
not punitive.72 Still, in litigation between private parties, courts typically withhold injunctive
relief if monetary penalties for the same underlying conduct are time-barred. While the Supreme
Court has never decided whether this rule—known as the concurrent remedies doctrine—applies
to the government, it has held that “an action on behalf of the United States in its governmental
capacity . . . is subject to no time limitation, in the absence of congressional enactment clearly
imposing it.”73 Heeding that admonition, circuit courts to consider the issue have held that the
federal government is not subject to the concurrent remedies doctrine.74 EPA thus generally
appears to be free to seek injunctive remedies even when 28 U.S.C. § 2462 precludes monetary
penalties.

Review of Administrative Enforcement Actions
The parties that EPA targets in administrative enforcement actions can challenge EPA’s authority
to act against them. When, where, and how they may do so depends on the type of enforcement
proceeding at issue, and, potentially, on the legal basis of their challenge.

Judicial Review of Administrative Compliance Orders Issued Without a Hearing
As noted above, several pollution control statutes authorize EPA to issue administrative
compliance orders without providing an opportunity for a hearing. For decades, lower courts
declined to review those orders unless and until EPA sued to enforce them.75 In Sackett v. EPA,
the Supreme Court rejected this approach, holding that recipients of EPA’s administrative
compliance orders could challenge those orders immediately under the APA rather than waiting
for EPA to bring suit.76

70 See, e.g., United States v. EME Homer City Generation, L.P., 727 F.3d 274, 284–85 (3d Cir. 2013) (holding that

violations of 42 U.S.C. § 7454(a) are complete when owners of major source of air pollution commence construction or
modification without a required permit in hand); accord United States v. Luminant Generation Co., L.L.C., 905 F.3d
874, 884 (5th Cir. 2018), reh'g en banc granted, 929 F.3d 316 (5th Cir. 2019); Midwest Generation, LLC, 720 F.3d at
647; Sierra Club v. Otter Tail Power Co., 615 F.3d 1008, 1015 (8th Cir. 2010); Nat’l Parks & Conservation Ass’n v.
Tenn. Valley Auth., 502 F.3d 1316, 1323 (11th Cir. 2007).
71 EME Homer City Generation, L.P., 727 F.3d at 284–85; Midwest Generation, LLC, 720 F.3d at 648; Otter Tail
Power Co., 615 F.3d at 1018; Nat’l Parks & Conservation Ass’n, Inc., 502 F.3d at 1323.
72 For a discussion of what constitutes a “penalty” within the meaning of 28 U.S.C. § 2462, see Kokesh v. SEC,
581 U.S. 455, 461–63 (2017).
73 E. I. Du Pont De Nemours & Co. v. Davis, 264 U.S. 456, 462 (1924).
74 Luminant Generation Co., 905 F.3d at 886–87; United States v. Telluride Co., 146 F.3d 1241, 1248–49 (10th Cir.
1998); United States v. Banks, 115 F.3d 916, 919 (11th Cir. 1997).
75 E.g., Sackett v. EPA, 622 F.3d 1139, 1143 (9th Cir. 2010), rev’d and remanded, 566 U.S. 120 (2012); Laguna
Gatuna, Inc. v. Browner, 58 F.3d 564 (10th Cir. 1995); S. Ohio Coal Co. v. Off. of Surface Mining, Reclamation &
Enf’t, 20 F.3d 1418 (6th Cir. 1994); S. Pines Assocs. by Goldmeier v. United States, 912 F.2d 713 (4th Cir. 1990);
Hoffman Grp., Inc. v. EPA, 902 F.2d 567 (7th Cir. 1990); Ross Incineration Servs., Inc. v. Browner, 118 F. Supp. 2d
837 (N.D. Ohio 2000); Sharp Land Co. v. EPA, 956 F. Supp. 691, 694 (M.D. La. 1996).
76 Sackett v. EPA, 566 U.S. 120, 131 (2012).
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Sackett concerned an EPA order requiring property owners to remedy alleged CWA violations by
conducting site restoration work.77 After receiving that order, the owners asked for an
administrative hearing, but EPA denied their request.78 The owners then brought suit under the
APA.79 The government argued that the suit was premature; the Supreme Court disagreed.80
The APA authorizes judicial review of (1) “final agency action” for which (2) “there is no other
adequate remedy in a court,” (3) so long as no other statute “preclude[s]” that review.81 According
to the Court, the property owners’ suit satisfied each of those conditions. EPA’s order was “final
agency action” because it both obliged the owners to restore their property and marked the
“‘consummation’ of [EPA’s] decisionmaking process,” which the agency demonstrated by
denying the hearing request.82 There was “no other adequate remedy in court” because the
property owners could not otherwise initiate suit themselves and because every day that they
waited for EPA to sue, “they accrue[d], by the Government’s telling, an additional $75,000 in
potential liability” for noncompliance.83 Finally, no other statute precluded judicial review
because “[n]othing in the [CWA] expressly” said so and any implied preclusive effect was
insufficient “to overcome the APA’s presumption of reviewability for all final agency action.”84

Agency and Judicial Review of Administrative Orders Issued After a Hearing
When ALJs and RJOs issue orders following hearings, EPA’s Consolidated Rules of Practice
allow aggrieved parties to seek review by the Environmental Appeals Board (EAB),85 a tribunal
of up to four EPA employees who are appointed by the EPA Administrator.86 The EAB reviews
matters “de novo,”87 which means that “it makes an independent determination without
deference” to the ALJs’ or RJOs’ “earlier analysis.”88 Pending EAB review, ALJ and RJO orders
are considered “interim” and have no binding effect.89 The EAB can then adopt, modify, or set
aside those interim orders,90 and its decisions are final and reviewable in federal court.91

77 Id. at 125.
78 Id.
79 Id.
80 Id. at 126–30.
81 5 U.S.C. §§ 701(a)(1), 704. See also CRS Legal Sidebar LSB10558, Judicial Review Under the Administrative

Procedure Act (APA), by Jonathan M. Gaffney (2024).
82 Sackett, 566 U.S. at 126–27.
83 Id. at 127–28.
84 Id. at 128–31.
85 40 C.F.R. § 22.30.
86 Changes to Regulations to Reflect the Role of the New Environmental Appeals Board in Agency Adjudications,
57 Fed. Reg. 5320 (Feb. 13, 1992); see also EAB GUIDE, supra note 55, at 2–3. No statute expressly authorizes the
EAB, leading some scholars to question whether the EAB is lawful. See William Funk, Is the Environmental Appeals
Board Unconstitutional or Unlawful?, 49 ENV’T L. 737 (2019).
87 De Novo, BLACK’S LAW DICTIONARY (12th ed. 2024).
88 EAB GUIDE, supra note 55, at 7.
89 40 C.F.R. § 22.27(c)(2), (d).
90 Id. § 22.30(f).
91 See, e.g., 42 U.S.C. § 11045(f)(1) (providing that “[a]ny person against whom a civil penalty is assessed under this
section [of the EPCRA] may obtain review thereof in the appropriate district court of the United States”); accord
15 U.S.C. § 2615(a)(3) (TSCA); 33 U.S.C. § 1319(g)(8)(A)–(B) (CWA); 42 U.S.C. § 300h-2(c)(6) (SDWA).
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Orders issued by ALJs and RJOs also become final if no one seeks EAB review within 45 days.92
In that case, EPA’s regulations state that the parties subject to the now-final order failed to exhaust
their administrative remedies and thus “waive[d] [their] rights to judicial review.”93 However, this
regulatory exhaustion requirement appears to have never been litigated, and if it were, it is
unclear if a court would give it controlling effect. Exhaustion of administrative remedies “is
required” when “Congress specifically mandates” it,94 but no statute mentions the EAB, let alone
directs parties to seek EAB review before judicial review.95 Absent a statutory mandate, the
doctrine of administrative exhaustion is prudential, and its application is committed to “sound
judicial discretion.”96
Even when an implied administrative exhaustion requirement is “fairly discernible” in statute,97
defendants in an enforcement action may still bypass agency proceedings and go directly to
federal district court if they contest an agency’s constitutional authority to proceed at all.98 Under
these circumstances, the Supreme Court has held that the harm from being subjected to an
unconstitutional agency proceeding is “‘a here-and-now injury’” that cannot be remedied once the
administrative proceeding is over and judicial review “kicks in.”99 The Court has also stressed
that when a litigant contests an agency’s “power generally” rather than “how that power was
wielded” in a particular case, its claims are generally “collateral” to administrative proceedings100
and “ill suited” to agency resolution.101 For these reasons, the Court has sometimes concluded
that certain constitutional challenges to agency authority are “not the type of claim Congress
intended to funnel through” generally applicable administrative proceedings.102

Administrative Enforcement and the Seventh Amendment
In recent years, some litigants have argued that administrative enforcement proceedings violate
the Seventh Amendment’s guarantee of trial by jury in “[s]uits at common law, where the value in
controversy shall exceed twenty dollars.” The Supreme Court considered that claim in SEC v.
Jarkesy, a case challenging the Securities and Exchange Commission’s (SEC’s) use of an inagency tribunal to levy administrative penalties for violations of antifraud provisions in securities

92 40 C.F.R. § 22.27(c).
93 Id. § 22.27(d).
94 McCarthy v. Madigan, 503 U.S. 140, 144 (1992) (emphasis added).
95 The statutory provisions that provide for judicial review of final EPA penalty orders, cited at note 91, supra, do not

mention the EAB or intermediate administrative appellate review generally. See also William Funk, Is the
Environmental Appeals Board Unconstitutional or Unlawful, 49 ENVTL. L. 737 (2019) (noting the absence of statutory
authorization for the EAB).
96 McCarthy, 503 U.S. at 144.
97 Thunder Basin Coal Co. v. Reich, 510 U.S. 200, 207 (1994) (quoting Block v. Cmty. Nutrition Inst., 476 U.S. 340,
351 (1984).
98 E.g., Axon Enter., Inc. v. FTC, 598 U.S. 175 (2023); Free Enter. Fund v. Pub. Co. Acct. Oversight Bd., 561 U.S. 477
(2010).
99 Axon Enter., 598 U.S. at 191 (quoting Seila L. LLC v. Consumer Fin. Prot. Bureau, 591 U.S. 197, 212 (2020)).
100 Id. at 193 (quoting Free Enter. Fund, 591 U.S. at 490).
101 ld. at 195 (quoting Carr v. Saul, 593 U.S. 83, 92 (2021)).
102 See id. at 184; Free Enter. Fund, 561 U.S. at 489–91 (allowing litigants to proceed first in district court with their
claims that removal protections afforded to certain inferior officers were unconstitutional). But see Elgin v. Dep’t of
Treasury, 567 U.S. 1, 17 (2012); Thunder Basin Coal Co. v. Reich, 510 U.S. at 216 (requiring administrative
exhaustion in cases where litigants raised both constitutional and nonconstitutional objections to agency action because
the agencies might dispose of the cases and afford complete relief on nonconstitutional grounds).
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laws.103 There, the Court applied a two-part test to determine whether administrative proceedings
were consistent with the Seventh Amendment.104
Because the Seventh Amendment jury right attaches to “[s]uits at common law”—i.e., legal
actions—the Court first asked whether SEC’s enforcement proceeding was “legal,” rather than
“equitable,” in nature.105 To parse the distinction between law and equity, the Court “consider[ed]
the cause of action and the remedy” sought106—though remedy was the “more important”
consideration107—and it asked whether the administrative proceeding was analogous to an action
that would have been heard in an 18th-century English court of law.108 If so, the jury right would
be implicated. If the proceeding was instead analogous to one that would have been heard in an
18th-century English court of equity, the jury right would not be implicated.109
While the historical distinction between law and equity is not always clear, the Court described
monetary penalties designed to punish and deter wrongdoing as “the prototypical common law
remedy.”110 On this basis alone, the Court concluded that SEC’s enforcement proceeding was
legal, rather than equitable,111 but the Court also stressed that the antifraud provisions in securities
laws “bore a close relationship” to “common law fraud,”112 further confirming the legal nature of
SEC’s enforcement proceeding.
Having concluded that SEC’s proceeding “implicate[d] the Seventh Amendment,” the Court next
asked whether the proceeding concerned “public,” rather than “private,” rights.113 If public rights
were at stake, the Court explained, then Congress could assign the proceeding to “an agency
tribunal without a jury, consistent with the Seventh Amendment.”114 While the Court has “not
definitively explained” the distinction between public and private rights,115 its “precedents have
recognized that the [public rights] doctrine covers matters ‘which arise between the Government
and persons subject to its authority in connection with the performance of the constitutional
functions of the executive or legislative departments.’”116 These include matters concerning
revenue collection, immigration, public lands, public benefits, and patents.117
That list is not exhaustive because Congress can create “new statutory public rights” and assign
their adjudication to agencies,118 but the Court cautioned that this congressional power is limited.
According to the Court, “[t]he public rights exception is, after all, an exception,” and practical

103 SEC v. Jarkesy, 603 U.S. 109, 115 (2024).
104 Id. at 121.
105 Id. at 122.
106 Id. at 123 (citing Tull v. United States, 481 U.S. 412, 417–18 (1987)).
107 Id. at 123 (quoting Tull, 481 U.S. at 421).
108 Id. at 122–23.
109 Id. For background on the concept of equity and equitable relief, see Sam Bray, A Student’s Guide to the Meanings

of “Equity,” REASON: VOLOKH CONSPIRACY (July 21, 2016, at 16:54 ET), https://reason.com/volokh/2016/07/21/astudents-guide-to-the-meanin/ [https://perma.cc/5DDQ-PZW6].
110 Jarkesy, 603 U.S. at 123.
111 Id. at 125.
112 Id. at 126.
113 Id. at 127.
114 Id.
115 Id. at 131 (quoting Oil States Energy Servs., LLC v. Greene’s Energy Grp., LLC, 584 U.S. 325, 334 (2018)).
116
Oil States, 584 U.S. at 334 (quoting Crowell v. Benson, 285 U.S. 22, 50 (1932)).
117 Jarkesy, 603 U.S. at 128–31.
118 See id. at 136–37 (quoting Atlas Roofing Co. v. Occupational Safety & Health Rev. Comm’n, 430 U.S. 442 (1977)).
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considerations “like increasing efficiency and reducing public costs are not enough to trigger”
it.119 Rather, Congress can “bypass the protection of the Seventh Amendment” only when it
creates statutory requirements with no common law antecedents. As an example, the Court cited
the Occupational Safety and Health (OSH) Act, a law whose requirements “resembled a detailed
building code” and were “‘unknown to the common law.’”120 The Court previously held that these
characteristics placed the OSH Act within the public rights exception.121 By contrast, the Court
held that securities fraud was “akin” to common law fraud and thus beyond Congress’s power to
assign to agency tribunals.122
It remains to be seen how Jarkesy’s two-step analysis will apply to administrative enforcement
proceedings under pollution-control statutes, but a recent decision by the U.S. Court of Appeals
for the Third Circuit suggests that at least some of those proceedings may concern public, rather
than private, rights. In Axalta Coating Systems v. FAA, the Third Circuit held that the FAA’s
proceedings to enforce the Hazardous Materials Transportation Act (HMTA) and impose
monetary penalties fell within the public rights exception.123 The court reasoned that the
underlying violation rested on “technical prescription[s]” that, like the requirements in the OSH
Act, brought no “common law soil with them.”124 While the HMTA defined “knowing” violations
by reference to two terms—“reasonable person” and “reasonable care”—with deep roots in the
common law tort of negligence, the court concluded that those terms were “relevant only to the
question whether the violating party knew of the violation” and thus did not control the public
rights analysis.125
Courts may conclude that other pollution control statutes with complex, highly technical
regulatory requirements likewise fall within the public rights exception.126 However, the law in
this area is evolving, and the Supreme Court has called for “close attention to the basis for each
asserted application of the [public rights] doctrine.”127 For now, at least, Jarkesy’s impact on
EPA’s enforcement authority remains unsettled.

Civil Judicial Enforcement
Every federal pollution control statute authorizes the federal government to sue alleged violators
in federal court, where juries (or in some cases, judges) determine liability, and where judges

119 Id. at 140.
120 Id.
121 See id. (discussing Atlas Roofing, 430 U.S. at 455).
122 Id. at 139.
123 144 F.4th 467, 471 (3d Cir. 2025).
124 Id. at 476 (quoting Jarkesy, 603 U.S. at 137). The prescriptions at issue in Axalta governed hazardous substance

“packagings for which retention of liquid is a basic function,” and required that those “packagings”
be capable of withstanding without leakage the greater of . . . [a]n internal pressure which produces
a gauge pressure of not less than 75kPa (11 psig) for liquids in Packing Group III of Class 3 or
Division 6.1; or 95 kPa (14 psig) for other liquids; or . . . [a] pressure related to the vapor pressure
of the liquid to be conveyed, determined by one of [three specified methods].
Id. at 477 (alterations in original) (quoting 49 C.F.R. § 173.27(c)(2)).
125 Id.
126 Cf. Tull v. United States, 481 U.S. 412, 420 (1987) (analogizing an action to enforce CWA Section 404 to an
“action in public nuisance” or “an action in debt” under the common law).
127 Jarkesy, 603 at 131.
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interpret the law, assess civil penalties, and craft injunctive relief.128 These laws generally permit
suits to enforce substantive statutory requirements or to compel compliance with the terms of
EPA-issued administrative orders.129

DOJ’s Role
“Except as otherwise authorized by law,” the Attorney General and her designees have sole
authority to “supervise all litigation to which the United States, an agency, or officer thereof is a
party.”130 Because no statute gives EPA independent litigating authority, EPA must refer cases to
DOJ to bring a civil judicial enforcement action.131 EPA’s referrals typically go to DOJ’s
Environment and Natural Resources Division (ENRD), which handles much of the department’s
environmental enforcement caseload.132
As a matter of policy, ENRD sues to enforce a statute only when asked to do so by the agency
charged with administering that statute.133 EPA’s referral is thus a precondition for civil judicial
enforcement action under most pollution control laws. However, EPA’s referral alone does not
guarantee a lawsuit. ENRD acts on most EPA referrals,134 but DOJ’s Office of Legal Counsel
(OLC), which issues legal opinions that are binding on the executive branch,135 has long
maintained that the Attorney General ultimately decides whether to bring litigation on behalf of
the United States.136

128 See generally Balt. & Carolina Line v. Redman, 295 U.S. 654, 657 (1935) (noting that, “in the absence of express or

implied consent to the contrary, issues of law are to be resolved by the court and issues of fact are to be determined by
the jury under appropriate instructions by the court”); see also Tull, 481 U.S. at 425 (noting the “constitutional right to
a jury trial to determine . . . liability on . . . legal claims”); id. at 427 (holding that Congress can, and typically does,
assign civil penalty determinations to judges).
129 See, e.g., 33 U.S.C. § 1319(d) (authorizing penalties in civil suits under the CWA against “any person who violates
any order issued by the Administrator”); 42 U.S.C. § 7413 (authorizing civil actions against any person who violates “a
requirement or prohibition of any . . . order . . . issued, or approved under” the CAA).
130 28 U.S.C. § 519; see also 28 U.S.C. § 516 (“Except as otherwise authorized by law, the conduct of litigation in
which the United States, an agency, or officer thereof is a party, or is interested, and securing evidence therefor, is
reserved to officers of the Department of Justice, under the direction of the Attorney General.”).
131 When it was debating the 1977 Amendments to the Clean Air Act, Congress considered granting EPA authority to
represent itself in civil litigation. S. REP. NO. 95-127, at 52 (1977). It “decided against such a transfer of representation
authority primarily on the strength of the personal commitment” by the Attorney General to “remedy” perceived
shortcomings in DOJ’s representation of EPA. Id. at 52–53. See also Memorandum of Understanding Between
Department of Justice and Environmental Protection Agency, 42 Fed. Reg. 48942 (Sep. 26, 1977) (discussing the roles
and responsibilities in cases that EPA refers to DOJ).
132 See 28 C.F.R. § 0.65 (2025) (DOJ regulations outlining ENRD’s responsibilities); see also U.S. Dep’t of Just., Just.
Manual § 5-1.200 (2024) [hereinafter Just. Manual] (authorizing ENRD “to exercise the functions and responsibilities
undertaken by the Attorney General in the Memorandum of Understanding dated June 15, 1977, between the
Department and the EPA”).
133 Just. Manual, supra note 132, § 5-12.111.B.
134 See Memorandum from Jeffrey Bossert Clark, Assistant Att’y Gen., Env’t & Nat. Res. Div., to ENRD Section
Chiefs & Deputy Section Chiefs, Enforcement Principles and Priorities n.17 (Jan. 14, 2021), https://www.justice.gov/
enrd/media/1412026/dl?inline [https://perma.cc/Y32K-XFEN] (noting that ENRD returns referrals to EPA only “on
occasion” after “thoroughly review[ing] such referrals”).
135 28 U.S.C. §§ 511–513; 28 C.F.R. § 0.25; Exec. Order No. 12146, §§ 1-401–1-402, 44 Fed. Reg. 42657 (July 18,
1979).
136 See The Att’y Gen.’s Role as Chief Litigator for the United States, 6 Op. O.L.C. 47, 48 (1982) (“[A]bsent clear
legislative directives to the contrary, the Attorney General has full plenary authority over all litigation, civil and
criminal, to which the United States, its agencies, or departments, are parties.”); see also United States v. Sandstrom,
22 F. Supp. 190, 191 (N.D. Okla. 1938) (holding that after a “case was referred to the Department of Justice,” the
(continued...)
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With exceptions not relevant here,137 DOJ generally does not sue other federal agencies. This
position reflects OLC’s long-held view that “‘lawsuits between two federal agencies are not
generally justiciable’” because agencies ultimately report to the President and “a lawsuit
involving the same person as both plaintiff and defendant” lacks adversity necessary to trigger
federal court jurisdiction.138 OLC has also opined that intra-executive branch suits raise
separation of powers concerns, since judicial resolution of agency disputes could constrain the
President’s constitutional authority “to supervise his subordinates and resolve disputes among
them.”139 Thus, while federal agencies are generally subject to requirements in pollution control
statutes, as a practical matter, they are generally not subject to civil judicial enforcement actions
by the federal government.

Legal Standard, Burden of Proof, and Statute of Limitations
The legal standard, ultimate burden of proof, and statute of limitations in civil judicial
enforcement actions mirror the standard, burden, and limitations period in administrative
enforcement hearings: liability is generally strict,140 negating the need to establish a defendant’s
knowledge or intent; the parties must prove the elements of their case by a preponderance of the
evidence; and suits for monetary penalties are subject to 28 U.S.C. § 2462’s five-year time-bar.141

Available Remedies
Pollution control statutes generally authorize the federal government to sue for monetary
penalties. Under most of these statutes, the government can seek penalties for the first time in a
civil judicial enforcement action,142 but under TSCA, FIFRA, and the Marine Protection,
Research, and Sanctuaries Act, DOJ can sue only to compel payment of EPA-assessed
administrative penalties.143
Civil judicial penalties are capped at an inflation-adjusted, daily maximum amount and are
assessed for each day that a violation persists.144 These maximum daily penalties are equal to or
higher than corresponding administrative penalties and are not subject to the aggregate limits that

referring agency “ceased to have any control over the same,” and the “Attorney General was not bound by the
recommendation of the” referring agency).
137 Exceptions to the general rule against interagency suit include suits involving independent agencies that are
insulated from presidential control and suits where the government plaintiff is not the real party in interest. For
examples of the former, see Bijal Shah, Executive (Agency) Administration, 72 STAN. L. REV. 641 (2020); for an
example of the latter, see United States v. Interstate Com. Comm’n, 337 U.S. 426 (1949).
138 Auth. of Dep’t of Hous. & Urban Dev. to Initiate Enf’t Actions Under the Fair Hous. Act Against Other Exec.
Branch Agencies, 18 Op. O.L.C. 101 (1994) (quoting Nuclear Regul. Comm’n’s Imposition of Civil Penalties on the
Air Force, 13 Op. O.L.C. 131, 138 (1989)).
139 INS Rev. of Final Order in Emp. Sanctions Cases, 13 Op. O.L.C. 370, 371 (1989).
140 See sources cited supra note 14.
141 See Ramirez v. T&H Lemont, Inc., 845 F.3d 772, 778 (7th Cir. 2016) (noting that “unless the governing statute . . .
specifies a higher burden, or the Constitution demands a higher burden because of the nature of the individual interests
at stake, proof by a preponderance of the evidence will suffice” in federal civil cases).
142 See 33 U.S.C. § 1319(d) (CWA); 42 U.S.C. § 300h-2(a)–(b) (SDWA); id. § 6928(g) (RCRA); id. § 7413(b) (CAA);
id. § 11045(b)(3) (EPCRA).
143 See 7 U.S.C. § 136l(a)(1) (FIFRA); 15 U.S.C. § 2615(a)(4) (TSCA); 33 U.S.C. § 1415(a) (MPRSA).
144 See, e.g., 33 U.S.C. § 1319(d) (CWA); 42 U.S.C. § 300h-2(a)–(b) (SDWA); id. § 6928(g) (RCRA); id. § 7413(b)
(CAA); id. § 11045(b)(3) (EPCRA).
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Congress set for some administrative penalties.145 As with administrative penalties, many statutes
provide factors for courts to consider when determining appropriate penalty amounts.146
Monetary penalties aside, two statutes authorize suits for seizure of certain substances. Under
FIFRA, the government can seek judicial permission to “seize[] for confiscation” a “pesticide or
device” that is adulterated, misbranded, unregistered, mislabeled, or improperly marketed.147
Similarly, TSCA authorizes suits “for seizure of an imminently hazardous chemical substance or
mixture.”148
Courts can also issue case-specific injunctive orders requiring parties to take or refrain from
taking certain actions.149 Injunctions can be preliminary or permanent. Preliminary injunctions
remain in place while a suit is pending, generally to maintain the status quo during litigation.150
Permanent injunctions are issued only after a final determination on the merits of a case.151
Some environmental statutes authorize injunctive relief,152 but even without such statute-specific
authorization, federal courts can issue injunctions under the general equitable authority conferred
by the Judiciary Act of 1789.153 That authority allows courts to craft injunctive relief so long as
that relief is consistent with “express and implied statutory limitation[s]”154 and falls “within the
broad boundaries of traditional equitable relief” available at the time of the founding.155
To obtain an injunction, a plaintiff must demonstrate
(1) that it has suffered an irreparable injury; (2) that remedies available at law, such as
monetary damages, are inadequate to compensate for that injury; (3) that, considering the
145 Maximum penalty amounts are provided in the statutory sections cited in note 144, supra. For current, inflation-

adjusted maximum penalties, see 40 C.F.R. § 19.4, tbl. 1.
146 See, e.g., 33 U.S.C. § 1319(d) (penalty considerations under the CWA); 42 U.S.C. § 7413(e) (penalty assessment
criteria under the CAA); 49 U.S.C. § 5122(a) (penalty considerations under the HMTA). While civil liability does not
turn on a defendant’s mental state, evidence of a defendant’s negligence or malign intent may be relevant to
determining civil penalty amount. E.g., 33 U.S.C. § 1319(g)(3). See also United States v. Harford Sands, Inc., 575 F.
Supp. 733, 735 (D. Md. 1983) (“While the defendant’s lack of knowledge . . . may affect its culpability and therefore
the amount of a civil penalty which would be appropriate, those sections of the [CWA] which the defendant is charged
with violating do not require that the violation be ‘willful’ or ‘knowing.’”); 33 U.S.C. § 1321(b)(7)(D) (providing for
higher civil penalties when violations result from “gross negligence or willful misconduct”).
147 7 U.S.C. § 136k(b)–(c).
148 15 U.S.C. § 2606(a)–(b)
149 CRS Report R46902, Nationwide Injunctions: Law, History, and Proposals for Reform, by Joanna R. Lampe (2021).
150 See Lackey v. Stinnie, 604 U.S. 192, 200 (2025) (“The purpose of a preliminary injunction is merely to preserve the
relative positions of the parties until a trial on the merits can be held.” (quoting Univ. of Tex. v. Camenisch, 451 U.S.
390, 395 (1981))).
151 As one scholar explained, the term “permanent injunction” is misleading because “[s]o-called ‘permanent
injunctions’ may be explicitly time limited, as when they are phased out after a year or two. And even if an injunction
is ostensibly permanent, the court may dissolve or modify it at any time.” Samuel Bray, The Purpose of the Preliminary
Injunction, 78 VAND. L. REV. 809 (April 2025).
152 See, e.g., 33 U.S.C. § 1319(b) (authorizing “civil action[s] for appropriate relief, including a permanent or
temporary injunction”); accord 15 U.S.C. §§ 2616(a)(1)(A)–(D), 2622(d) (TSCA); 42 U.S.C. § 6928(a) (RCRA); id.
§ 7413(b) (CAA).
153 See Trump v. CASA, Inc., 606 U.S. 831, 841 (2025) (noting that the Judiciary Act of 1789 “is what authorizes the
federal courts to issue equitable remedies” (quoting S. Bray & E. Sherwin, Remedies 442 (4th ed. 2024))).
154 Armstrong v. Exceptional Child Ctr., Inc., 575 U.S. 320, 327 (2015); see also Miller v. French, 530 U.S. 327, 340
(2000) (holding that courts “should not construe a statute to displace courts’ traditional equitable authority absent the
‘clearest command,’ or an ‘inescapable inference’ to the contrary” (quoting Califano v. Yamasaki, 442 U.S. 682, 705
(1979), and Porter v. Warner Holding Co., 328 U.S. 395, 398 (1946))).
155 CASA, Inc., 606 U.S. at 846 (quoting Grupo Mexicano de Desarrollo S.A. v. All. Bond Fund, Inc., 527 U.S. 308,
322 (1999)).
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balance of hardships between the plaintiff and defendant, a remedy in equity is warranted;
and (4) that the public interest would not be disserved by a[n] . . . injunction.156

The Supreme Court has stressed that injunctions are “extraordinary” relief and are not “granted as
a matter of course.”157 Even so, the Court has noted that “[e]nvironmental injury, by its nature,
can seldom be adequately remedied by money damages and is often permanent or at least of long
duration, i.e., irreparable.”158 While this does not create a “presumption” in favor of injunctive
relief in environmental cases, it does mean that “the balance of harms will usually favor the
issuance of an injunction to protect the environment.”159
Commonly sought injunctions in environmental cases include orders requiring defendants to
clean up polluted sites or take actions to ensure prospective compliance with statutory obligations
or administrative orders.160
Court-issued injunctions are enforceable through contempt orders.161 Parties held in contempt
may be subject to fines or imprisonment.162

Settlement Agreements and Consent Decrees
If the parties in a civil judicial enforcement action agree to terms, they can voluntarily resolve
their dispute through settlement. EPA has a say in whether to settle cases,163 but as with the
decision to bring suit, OLC maintains that ultimate settlement authority rests with DOJ.164
Broadly speaking, settlements may take one of two forms. First, litigants can memorialize their
agreement in an out-of-court settlement. When this happens, the parties often stipulate to
voluntary dismissal of the underlying enforcement action, and the court lacks continuing
156 Monsanto Co. v. Geertson Seed Farms, 561 U.S. 139, 156–57 (2010). A plaintiff that seeks a preliminary injunction

before liability is resolved must also show that it is likely to succeed on the merits of its claim. Winter v. Nat. Res. Def.
Council, Inc., 555 U.S. 7, 20 (2008).
157 Id. at 165.
158 Amoco Prod. Co. v. Vill. of Gambell, 480 U.S. 531, 545 (1987).
159 Id.
160 See, e.g., Meghrig v. KFC W., Inc., 516 U.S. 479, 484 (1996) (holding that a “plain reading” of RCRA’s remedial
scheme authorizes courts to issue “a mandatory injunction, i.e., one that orders a responsible party to ‘take action’ by
attending to the cleanup and proper disposal of toxic waste, or a prohibitory injunction, i.e., one that ‘restrains’ a
responsible party from further violating RCRA”); Interfaith Cmty. Org. v. Honeywell Int’l, Inc., 399 F.3d 248, 264 (3d
Cir. 2005) (affirming a district court’s entry of permanent injunction under RCRA requiring the defendant to excavate
and dispose of contaminated waste); U.S. Pub. Int. Rsch. Grp. v. Atl. Salmon of Maine, LLC, 339 F.3d 23 (1st Cir.
2003) (affirming a district court’s entry of permanent injunction requiring operational changes at a commercial fish
farm to ensure prospective compliance with the CWA); United States v. Deaton, 332 F.3d 698, 713 (4th Cir. 2003)
(affirming district court’s injunctive order requiring defendant to take remedial action to restore wetlands filled in
violation of the CWA); EPA v. Env’t Waste Control, Inc., 917 F.2d 327, 331–32 (7th Cir. 1990) (affirming district
court’s injunction requiring defendants to permanently close a landfill to address RCRA violations); Gordon-Darby
Holdings, Inc. v. N.H. Dep’t of Safety, Comm’r, No. 25-CV-508-LM-AJ, 2026 WL 207187, at *19 (D.N.H. Jan. 27,
2026) (granting a motion for preliminary injunction and ordering a state agency “to take all steps necessary to resume
and ensure the continued implementation and enforcement of” the state’s “vehicle inspection and maintenance
program” as required under the CAA).
161 11A WRIGHT & MILLER’S FEDERAL PRACTICE & PROCEDURE § 2960 (3d. ed. 1998). See also Nken v. Holder,
556 U.S. 418, 428 (2009) (noting that an injunction “directs the conduct of a party . . . with the backing of [the court’s]
full coercive powers”).
162 See 18 U.S.C. § 401 (authorizing courts to punish “contempt of [their] authority”).
163 See Memorandum of Understanding Between Department of Justice and Environmental Protection Agency, 42 Fed.
Reg. 48943 (Sep. 26, 1977) (“The settlement of any case in which [DOJ] represents [EPA] . . . shall require
consultation with and concurrence of both the [EPA] Administrator and the Attorney General.”).
164 The Att’y Gen.’s Role as Chief Litigator for the United States, 6 Op. O.L.C. 47, 59–60 (1982).
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jurisdiction to compel compliance with the terms of the settlement agreement.165 A party seeking
to enforce those terms would have to bring a separate suit akin to a breach of contract action, with
the settlement agreement serving as the underlying contract.
Alternatively, settling parties can ask the court to incorporate their settlement terms in an order
called a consent decree.166 If the court agrees to do so, the resulting consent decree “is subject to
the rules generally applicable to other judgments and decrees.”167 Thus, as with other judgments,
consent decrees can be modified or vacated only with leave of the court;168 courts retain
jurisdiction to monitor compliance with, and enforce, consent decrees;169 and courts can hold
noncompliant parties in contempt.170 Parties to a consent decree can ask the court to enforce its
terms, but a consent decree is generally “not enforceable directly or in collateral proceedings by
those who are not parties to it.”171
DOJ will seek entry of a consent decree in “an action to enjoin discharges of pollutants” only
after “persons (natural or corporate) who are not named as parties to the action” have a 30-day
opportunity to comment on the proposed decree.172 After DOJ considers those comments, which it
must also file with the court, the department either withdraws the proposed decree or asks that the
court enter it.173
Before entering a consent decree, a court must determine for itself if the parties’ proposed terms
are “reasonable,” “faithful to the . . . objectives” of the statute that gave rise to the suit, “and fair
(both procedurally and substantively).”174 Because this inquiry is “guided by the general principle
that settlements are encouraged,” courts generally defer to the parties’ proposed terms.175 That
deference is heightened “in very complex and technical regulatory contexts,” where “the
165 See FED. R. CIV. P. 41(a)(1)(A)(ii) (allowing plaintiffs to voluntarily dismiss an action without a court order by

filing “a stipulation of dismissal signed by all parties who have appeared”); see also Kokkonen v. Guardian Life Ins.
Co. of Am., 511 U.S. 375, 380–82 (1994) (holding that courts have no inherent authority to enforce settlements terms
that are not included in a court order).
166 Rufo v. Inmates of Suffolk Cnty. Jail, 502 U.S. 367, 378 (1992); see also Buckhannon Bd. & Care Home, Inc. v. W.
Va. Dep’t of Health & Hum. Res., 532 U.S. 598, 604–05 (2001) (noting that a court-ordered consent decree, like a
“judgment on the merits,” creates a “judicially sanctioned change in the legal relationship of the parties”).
167 Rufo, 502 U.S. at 378.
168 If a party to a consent decree wants a court to modify or repeal that decree, it must file a motion under Federal Rule
of Civil Procedure 60(b), which allows courts to “relieve a party or its legal representative from a final judgment, order,
or proceeding” if the order “has been satisfied, released, or discharged,” is “based on an earlier judgment that has been
reversed or vacated,” is “no longer equitable,” or for “any other reason that justifies relief.” Fed. R. Civ. P. 60(b)(5)–
(6); see also Rufo, 502 U.S. at 378 (holding that consent decrees are subject to Rule 60(b)).
169 Beckett v. Air Line Pilots Ass’n, 995 F.2d 280, 282 (D.C. Cir. 1993) (noting “the well-established principle that a
trial court retains jurisdiction to enforce its consent decrees”).
170 See Spallone v. United States, 493 U.S. 265, 276 (1990) (“In selecting a means to enforce the consent judgment, the
District Court was entitled to rely on the axiom that ‘courts have inherent power to enforce compliance with their
lawful orders through civil contempt.’” (quoting Shillitani v. United States, 384 U.S. 364, 370 (1966))).
171Blue Chip Stamps v. Manor Drug Stores, 421 U.S. 723, 750 (1975).
172 28 C.F.R. § 50.7(a)–(b).
173 Id. § 50.7(b); see also Just. Manual, supra note 132, § 5-12.620.B.
174 City of Bangor v. Citizens Commc’ns Co., 532 F.3d 70, 93 (1st Cir. 2008) (quoting United States v. Charles George
Trucking, Inc., 34 F.3d 1081, 1084 (1st Cir. 1994)); accord United States v. North Carolina, 180 F.3d 574, 581 (4th
Cir. 1999); United States v. Oregon, 913 F.2d 576, 580 (9th Cir. 1990). To assess reasonableness and fairness, courts
consider “the basic legality of the decree,” “whether the terms of the decree, including its enforcement mechanism, are
clear,” “whether the consent decree reflects a resolution of the actual claims in the complaint,” and “whether the
consent decree is tainted by improper collusion or corruption of some kind.” SEC v. Citigroup Glob. Mkts., Inc.,
752 F.3d 285, 295 (2d Cir. 2014).
175 North Carolina, 180 F.3d at 581.
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settlement has been advanced for entry as a decree by a government actor committed to the
protection of the public interest and specially trained and oriented in the field,”176 so courts are
particularly unlikely to reject proposed consent decrees in government-led environmental
enforcement actions. That said, a court presented with a proposed consent decree “is not merely a
rubber stamp,”177 and judges sometimes refuse to enter decrees proposed by the government.178

Citizen Suits
Most of the federal pollution control statutes include citizen suit provisions that authorize
nonfederal parties to act as private attorneys general by suing other private parties or government
actors to address alleged violations of a statute. At the federal level, citizen suit provisions
originated in the Clean Air Act Amendments of 1970 and were intended as a way to
(1) supplement enforcement in light of agencies’ limited resources to assure compliance and
(2) encourage the executive branch to take action where appropriate.179 While citizen suits can
take several forms, this report focuses on the use of citizen suits as private enforcement actions,
that is, to address violations of pollution control requirements.180
Most major federal environmental statutes include a citizen suit provision, but some do not. Table
A-2 lists the citizen suit provisions in major federal pollution control statutes.

Elements of Citizen Suits
While the exact wording of citizen suit provisions varies from statute to statute, many provisions
share a common formulation.
Plaintiffs and defendants. In general, citizen suit provisions allow suits by “any citizen” or “any
person,” which is defined to include state and local governments.181 Plaintiffs may file lawsuits

176 United States v. Comunidades Unidas Contra La Contaminacion, 204 F.3d 275, 280 (1st Cir. 2000).
177 Citigroup Glob. Mkts., 752 F.3d at 293.
178 See, e.g., EEOC v. Int’l Ass’n of Bridge, Structural & Ornamental Ironworkers Loc. 580, No. 25-44-CV, 2026 WL

392327, at *5 (2d Cir. Feb. 12, 2026) (affirming district court’s refusal to enter proposed consent decree).
179 S. REP. NO. 91-1196, at 36–39 (1970) (“Government initiative in seeking enforcement under the Clean Air Act has
been restrained. Authorizing citizens to bring suits for violations of standards should motivate governmental agencies
charged with the responsibility to bring enforcement and abatement proceedings.”); see also STAFF OF S. COMM. ON
PUBLIC WORKS, 93RD CONG., A LEGISLATIVE HISTORY OF THE CLEAN AIR ACT AMENDMENTS OF 1970, at 214 (Comm.
Print 1974) (letter from Nixon Administration to Sen. Jennings Randolph, Chair, Senate Committee on Public Works);
Natural Res. Def. Council, Inc. v. Train, 510 F.2d 692, 727–30 (D.C. Cir. 1974) (reproducing comments on the Senate
floor by Sen. Muskie and Sen. Hart and statement by Ramsey Clark). For further discussion of the legislative history of
federal citizen suit provisions, see Robert D. Snook, Environmental Citizen Suits and Judicial Interpretation: First
Time Tragedy, Second Time Farce, 20 W. NEW ENG. L. REV. 311, 316–20 (1998). For a discussion of the state-law
origins of citizen suit provisions, see James R. May, The Availability of State Environmental Citizen Suits, 18 NAT.
RES. & ENV’T 53, 55 (2004); Scott W. Stern, Standing for Everyone: Sierra Club v. Morton, Supreme Court
Deliberations, and a Solution to the Problem of Environmental Standing, 30 FORDHAM ENV’T L. REV. 21, 88–97
(2019); Susan George, William J. Snape, III, & Rina Rodriguez, The Public in Action: Using State Citizen Suit Statutes
to Protect Biodiversity, 6 U. BALT. J. ENV’T L. 1, 17–25 (1997).
180 As noted in the Introduction, discussion of the legal issues arising in so-called “mandatory duty” suits—where a
citizen sues a federal agency for failure to take a required action under one of the applicable laws—is beyond the scope
of this report.
181 See, e.g., 42 U.S.C. § 7602(e) (CAA); 33 U.S.C. §§ 1362(5), 1365(g) (CWA); 42 U.S.C. § 9659 (CERCLA);
15 U.S.C. § 2619 (TSCA).
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against “any person,” which includes the federal government and other governmental entities to
the extent permitted by the Eleventh Amendment.182
Violations. Citizen suits generally may allege that a defendant has violated a statute or
enumerated sections of a statute, as well as a regulation, a permit, order, or limitation issued
thereunder.183 This includes allegations that a federal facility violated pollution-control
standards.184
Notice and timing requirements. Many statutes limit the availability of citizen suits by requiring
that putative plaintiffs first notify defendants and EPA of their intent at least a specified length of
time before filing a lawsuit, thereby giving the alleged violator an opportunity to come into
compliance with the statute and EPA an opportunity to take action.185 For example, the CWA
citizen suit provision requires that plaintiffs provide at least 60 days’ notice of the alleged
violation to the EPA Administrator, the state in which the alleged violation occurred, and the
alleged violator(s) before filing a suit alleging violations of the statute.186
Government involvement. Several mechanisms provide for additional notification to the federal
government and an opportunity for government involvement in litigation. First, citizen suit
provisions generally bar private enforcement actions if EPA or a state has undertaken and is
“diligently prosecuting” a civil or criminal action to address the same violations.187 In such cases,
however, a citizen plaintiff may intervene in the federal or state enforcement action.188 Second,
EPA generally may intervene as a matter of right in citizen suits.189 Third, in addition to the notice
requirements described above, plaintiffs must also notify the federal government after filing a
complaint and after finalizing a proposed consent decree.190 The court may not enter (i.e.,
approve) a consent decree any earlier than 45 days after EPA and DOJ are notified; during that
window, the United States may comment on or object to the proposed consent decree.191

182 E.g., 42 U.S.C. § 7604(a)(1) (CAA); 33 U.S.C. § 1365(a)(1) (CWA); 42 U.S.C. § 9659(a)(1) (CERCLA); 15 U.S.C.

§ 2619(a)(1) (TSCA). The Eleventh Amendment bars federal courts from construing their judicial power to allow suits
against states by citizens of another state or by foreign states or their citizens or subjects. U.S. CONST. amend. XI; Libr.
of Cong., Overview of Eleventh Amendment, Suits Against States, CONSTITUTION ANNOTATED,
https://constitution.congress.gov/browse/essay/amdt11-1/ALDE_00013675/ (last visited Apr. 27, 2026).
183 See, e.g., 42 U.S.C. § 7604(a)(1) (CAA), (a)(3); 33 U.S.C. § 1365(a)(1) (CWA); 42 U.S.C. § 9659(a)(1) (CERCLA);
15 U.S.C. § 2619(a)(1) (TSCA).
184 In its report accompanying the CAA amendments that added the citizen suit provision, the Senate Committee on
Public Works noted that authorizing citizen suits against the government was important because federal facilities
“generate considerable air pollution” and “have been notoriously laggard in abating pollution and in requesting
appropriations to develop control measures.” S. REP. NO. 91-1196, at 37 (1970).
185 See, e.g., 42 U.S.C. § 7604(b); 33 U.S.C. § 1365(b); 42 U.S.C. § 9659(d); 15 U.S.C. § 2619(b)(1); Gwaltney of
Smithfield, Ltd. v. Chesapeake Bay Found., 484 U.S. 49, 60 (1986); S. REP. NO. 91-1196, at 37 (1970). Some citizen
suit provisions impose more restrictive timing requirements. A citizen suit to challenge the adequacy of a CERCLA
cleanup may not be filed until after a cleanup is completed, and persons may not challenge a removal action at a site
where a longer-term remedial action is planned. 42 U.S.C. § 9613(h).
186 33 U.S.C. § 1365(b)(1). For citizen suits alleging violations of Sections 306 (relating to National Standards of
Performance) or 307(a) (relating to standards for discharges of toxic pollutants), plaintiffs must still provide notice but
may file a lawsuit immediately after doing so. Id. § 1365(b).
187 E.g., 42 U.S.C. § 7604(b)(1)(B); 33 U.S.C. § 1365(b)(1)(B); 42 U.S.C. § 9659(d)(2); 15 U.S.C. § 2619(b)(1)(B).
188 E.g., 42 U.S.C. § 7604(b)(1)(B); 33 U.S.C. § 1365(b)(1)(B); 15 U.S.C. § 2619(b)(1)(B). The CERCLA citizen suit
provision does not have a comparable mechanism for citizen plaintiff intervention. 42 U.S.C. § 9659.
189
E.g., 42 U.S.C. § 7604(c)(2); 33 U.S.C. § 1365(c)(2); 42 U.S.C. § 9659(g); 15 U.S.C. § 2619(c)(1).
190 E.g., 42 U.S.C. § 7604(c)(3); 33 U.S.C. § 1365(c)(3).
191 Id.
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Remedies. Depending on the statute at issue, litigants who are successful may obtain injunctive
relief, recover litigation costs, and (in more limited instances) secure civil penalties to be paid to
the U.S. Treasury.192 Citizen suits are intended to redress harm to the environment, rather than to
individuals, resulting from statutory violations.193 Plaintiffs may be able to pursue state-law tort to
vindicate private interests and address personal injury, property damage, or economic loss.194
Citizen suit provisions expressly preserve rights and remedies under other laws, including state
tort laws.195

Article III Limitations on Citizen Suits
The Supreme Court has recognized various restraints on the availability of citizen suits under
Article III of the Constitution, which limits the scope of federal court jurisdiction to adjudicating
“Cases” and “Controversies.”196 The doctrine of standing, which generally refers to a litigant’s
right to have a court rule upon the merits of particular claims for which that litigant seeks judicial
relief, derives from this limitation.197
While citizen suit provisions confer jurisdiction on federal courts to hear private enforcement
claims, they do not confer standing on plaintiffs to bring suit.198 Instead, litigants who wish to file
a citizen suit must meet the basic Article III standing requirements by showing that (1) they have
suffered an injury in fact that is (2) fairly traceable to the allegedly unlawful actions of the
opposing party and (3) likely redressable by a favorable judicial decision.199 In the environmental
context, plaintiffs typically must demonstrate that they themselves have been harmed or
anticipate harm as a result of the violation and that such harm could be addressed by a court
order, such as an injunction directing the defendant to stop ongoing pollution. Additionally, courts
have developed a set of “prudential” standing principles, including that a litigant may not assert
the rights of third parties not before the court, seek redress for a generalized grievance, or assert
an interest that does not fall within the zone of interests arguably protected or regulated by the
statute or constitutional provision underlying the litigant’s claims.200 Article III also requires that
“an actual controversy must exist not only at the time the complaint is filed, but through all stages
192 E.g., 42 U.S.C. § 7604(a) (authorizing injunctive relief and civil penalty awards), (d) (allowing litigation costs);

33 U.S.C. § 1365(a) (authorizing injunctive relief and civil penalty awards), (d) (allowing litigation costs); 42 U.S.C.
§ 9659(c) (authorizing injunctive relief and civil penalty awards), (f) (allowing litigation costs); 15 U.S.C. § 2619(a)(1)
authorizing courts to “restrain” relevant violations), (c)(2) (allowing litigation costs).
193 See Barry Breen, Citizen Suits for Natural Resource Damages: Closing a Gap in Federal Environmental Law,
24 WAKE FOREST L. REV. 851, 870 (1989).
194 See Mark Latham, Victor E. Schwartz, & Christopher E. Appel, The Intersection of Tort and Environmental Law:
Where the Twains Should Meet and Depart, 80 FORDHAM L. REV. 737, 750–758 (2011); Albert C. Lin, The Unifying
Role of Harm in Environmental Law, 2006 WISC. L. REV. 897, 905–911 (2006).
195 E.g., 42 U.S.C. § 7604(e); 33 U.S.C. § 1365(c); 42 U.S.C. § 9659(h); 15 U.S.C. § 2619(c)(3); see also S. REP. NO.
91-1196, at 38 (1970).
196 U.S. CONST. art. III, § 2.
197 See Libr. of Cong., Overview of Standing, CONSTITUTION ANNOTATED,
https://constitution.congress.gov/browse/essay/artIII-S2-C1-6-1/ALDE_00012992/ (last visited Apr. 27, 2026).
198 See, e.g., Middlesex Cnty. Sewerage Auth. v. Sea Clammers, 453 U.S. 1, 16 (1981).
199 TransUnion LLC v. Ramirez, 594 U.S. 413, 423 (2021).
200 Bennett v. Spear, 520 U.S. 154, 162 (1997); Allen v. Wright, 468 U.S. 737, 750–51 (1984). The Court has said this
zone-of-interests test is a prudential standing requirement that can be modified or abrogated by Congress. See Bennett,
520 U.S. at 164–165. For example, the Court held that ESA’s citizen suit provision expanded the zone of interests
protected by the statute to economic as well as environmental interests, reasoning that the ESA’s provision that “any
person may commence a civil suit” constituted “an authorization of remarkable breadth,” including in comparison to
some other citizen suit provisions, and also noting that the provision’s purpose of encouraging private enforcement
supported a conclusion of expanded standing. Id.
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of the litigation.”201 If the controversy existing at the time a lawsuit was filed is no longer “live”
due to a change in the law or in the status of the parties involved, the case is considered moot, and
federal courts must generally decline to hear (or continue to preside over) it.202
Initially, courts interpreted Article III requirements generously toward environmental plaintiffs,
concluding that plaintiffs have satisfied the injury-in-fact requirement by alleging that challenged
conduct threatened aesthetic harm, harm to their interest in observing or studying certain animals,
or widespread harm shared by many others.203 While those harms are still recognized today,
beginning in the 1980s, the Supreme Court took a more demanding approach to standing,
particularly in citizen suits.204 The Court’s 1992 decision in Lujan v. Defenders of Wildlife
articulated the current, more stringent standard for the “injury in fact” prong of Article III
standing.205 In Lujan, the Court ruled that affidavits that an organization’s members intended to
travel internationally to observe endangered species were insufficient to establish standing to
challenge a policy excluding overseas projects from certain Endangered Species Act
requirements.206 The affidavits included statements that the members had previously traveled to
observe endangered species and expressed a general intent to do so in the future, but did not
identify concrete plans or a specific time when the members intended to travel again.207
Explaining that it was “substantially more difficult” to establish standing if a plaintiff “is not
himself the object of the government action or inaction he challenges,” the Court reasoned that
the affiants’ intent to return to the development sites, without a description of concrete plans,
could not support a finding of “actual or imminent” injury.208
Other cases have addressed Article III as it relates to the timing of violations alleged in citizen
suits. In general, the Court has held that citizen suits may proceed only where there are continuing
(rather than past) violations, but that the voluntary cessation of unlawful conduct after a lawsuit
has been filed does not suffice to moot the case because, absent a showing to the contrary, the
defendant could resume the unlawful conduct.209 Similarly, with respect to the redressability
prong of the Article III standing test, the Court has ruled that civil money penalties and certain
forms of injunctive relief do not establish redressability for past violations because any remedy
for past violations amounts to “vindication of the rule of law” rather than remediation of
plaintiffs’ own injuries.210 The Court has further held that the injunctive relief sought by the
plaintiffs—providing for inspection authority and compelling the production of compliance
reports—would not remediate a past wrong, and the plaintiffs had not alleged an ongoing or

201 Kingdomware Techs., Inc. v. United States, 579 U.S. 162, 168 (2016) (quoting Already, LLC v. Nike, Inc., 568 U.S.

85, 90–91 (2013)).
202 Id.; Liner v. Jafco, 375 U.S. 301, 306 n.3 (1964).
203 Sierra Club v. Morton, 405 U.S. 727, 734 (1972); United States v. Students Challenging Regul. Agency Procs.
(SCRAP), 412 U.S. 669, 687–88 (1973); Japan Whaling Ass’n v. Am. Cetacean Soc’y, 478 U.S. 221, 230 n.4 (1986);
see also Ann E. Carlson, Standing for the Environment, 45 UCLA L. REV. 931, 939-42 (1998).
204 See Cassandra Stubbs, Is the Environmental Citizen Suit Dead? An Examination of the Erosion of Standards of
Justiciability for Environmental Citizen Suits, 26 N.Y.U. REV. L. & SOCIAL CHANGE 77, 82–83 (2001); Carlson, supra
note 203, at 938.
205 504 U.S. 555 (1992).
206 Id. at 563–64.
207 Id.
208 Id. at 564. A plurality of the Court also found that the plaintiffs had not satisfied the Article III redressability
requirement. Id. at 571.
209 Gwaltney v. Chesapeake Bay Found., 484 U.S. 49, 56–63 (1987); Friends of the Earth, Inc. v. Laidlaw Env’t Servs.
(TOC), Inc., 528 U.S. 167, 173–74, 189 (2000).
210 Steel Co. v. Citizens for a Better Env’t, 523 U.S. 83, 106 (1998).
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imminent violation.211 By contrast, in the case of a continuing violation, civil money penalties
may “afford redress to citizen plaintiffs who are injured or threatened with injury as a
consequence of ongoing unlawful conduct”—even though they are payable to the U.S. Treasury
and not to plaintiffs—insomuch as they “encourage defendants to discontinue current violations
and deter them from committing future ones.”212
One example of recent litigation in the citizen suit arena focused on the traceability component of
the Article III standing test and the degree to which plaintiffs must trace specific injuries (as
opposed to injuries of a certain type) to alleged statutory violations.213 In Environment Texas
Citizen Lobby, Inc. v. ExxonMobil Corp., the district court found that the plaintiffs had standing
and had established traceability for 3,651 days of permit violations at a Texas refinery, applying
the requirement that the plaintiffs show that each alleged violation “(1) causes or contributes to
the kinds of injuries they allege and (2) has a specific geographic or other causative nexus such
that the violation could have affected their members.”214 After a divided panel of the U.S. Court
of Appeals for the Fifth Circuit, the full Fifth Circuit ordered rehearing en banc, vacated its earlier
panel opinions, and, almost two years later, issued a short per curiam opinion affirming the
district court’s ruling without addressing standing.215 The Supreme Court declined to take up the
case after the Fifth Circuit’s fractured holding, and the peculiar procedural history of the case
means there is no precedential decision on the standing question in the Fifth Circuit.216 As a
result, there is still legal uncertainty regarding the traceability showing plaintiffs must make.217

Additional Constitutional and Policy Considerations
Some critics of the citizen-suit model have expressed concerns that citizen suits may violate
separation-of-powers principles and infringe on powers delegated to the executive branch in
Article II of the Constitution by permitting private citizens to exercise an enforcement function
vested solely in the executive branch.218 Critics of citizen suits also assert that citizen suits allow
211 Id. at 108.
212 Friends of the Earth, 528 U.S. at 187–88.
213 Env’t Tex. Citizen Lobby, Inc. v. ExxonMobil Corp., 123 F.4th 309 (5th Cir. 2024) (mem.); 47 F.4th 408, 417, 419

(5th Cir. 2022).
214 Env’t Tex. Citizen Lobby, Inc. v. ExxonMobil Corp., 524 F. Supp. 3d 547, 555 (S.D. Tex. 2021).
215 Env’t Tex. Citizen Lobby, Inc., 47 F.4th 408; Env’t Tex. Citizen Lobby, Inc., 123 F.4th 309.
216 ExxonMobil Corp. v. Env’t Tex. Citizen Lobby, Inc., No. 24-982, 145 S. Ct. 2845 (June 30, 2025) (mem.) (denying
certiorari).
217 On the same day that it denied the cert petition in ExxonMobil Corp. v. Environment Texas Citizen Lobby, the
Supreme Court also declined to review the U.S. Court of Appeals for the Ninth Circuit’s holding in a different case that
environmental plaintiffs could file a CWA citizen suit in federal court to enforce state law requirements that had been
incorporated into Washington State’s Industrial Stormwater General Permit, and which were broader than federal
requirements. Port of Tacoma v. Puget Soundkeeper All., No. 24-350, 145 S. Ct. 2849 (June 30, 2025) (mem.). That
case turned on the specific language of the CWA’s citizen suit provision, and its applicability to other statutes is
unclear.
218 See Friends of the Earth, 528 U.S. at 197 (Kennedy, J., concurring) (noting that “[d]ifficult and fundamental
questions are raised when we ask whether exactions of public fines by private litigants, and the delegation of Executive
power which might be inferable from the authorization, are permissible in view of the responsibilities committed to the
Executive by Article II of the Constitution of the United States”); id. at 209 (Scalia, J., dissenting) (cautioning that
“[b]y permitting citizens to pursue civil penalties payable to the Federal Treasury, the [CWA] . . . turns over to private
citizens the function of enforcing the law,” empowering plaintiffs to “[act] as a self-appointed mini-EPA”); see also
Brief of Richard Epstein and Jeremy Rabkin as Amici Curiae in Support of Plaintiff United States of America, United
States v. DTE Energy Co., No. 10-cv-13101, 2020 WL 10730046 (E.D. Mich. Dec. 30, 2020); Charles S. Abell,
Ignoring the Trees for the Forests: How the Citizen Suit Provision of the Clean Water Act Violates the Constitution’s
Separation of Powers Principle, 81 VA. L. REV. 1957 (1995).
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private litigants to dictate enforcement priorities without the oversight and accountability that
accompany government enforcement and that citizen suits do not necessarily result in meaningful
environmental improvement.219
Advocates for citizen suits argue that such suits provide a necessary backstop where the
government lacks the resources to fully enforce environmental laws, to buffer against varying
levels of enforcement across administrations, or where regulated entities have undermined the full
federal implementation of environmental statutes.220 They also argue that the statutory provisions
authorizing citizen suits include various mechanisms authorizing the executive branch to “protect
its policy and strategy choices,” whether by engaging in its own enforcement action and thus
barring the availability of a citizen suit, intervening in a citizen suit or participating as an amicus
curiae, or commenting on a proposed citizen suit consent decree.221 According to some scholars,
these limitations also ensure that the President retains control over the enforcement of federal
laws consistent with the Take Care Clause.222 To date, while some individual Supreme Court
Justices have expressed concerns regarding the constitutionality of citizen suits, the Court as a
whole has not indicated a willingness to consider these issues.223

Criminal Enforcement
Many environmental statutes authorize criminal penalties for certain violations, which can result
in jail time for individuals, as well as potential criminal fines and restitution for both individuals
and corporations.224 As a consequence, the government carries a heavier burden of proof in
criminal cases than in administrative or civil judicial enforcement matters and must prove the
defendant’s guilt beyond a reasonable doubt.225 Criminal prosecutors within DOJ, whether in the
U.S. Attorneys’ Offices or ENRD, bring criminal cases under the pollution control laws on behalf
of the federal government.226 A felony criminal case typically begins when prosecutors obtain an
indictment from a grand jury upon a finding of probable cause that an offense has been

219 E.g., Jonathan H. Adler, Stand or Deliver: Citizen Suits, Standing, and Environmental Protection, 12 DUKE ENV’T

L. & POL’Y F. 39, 43, 49–50 (2001) (arguing that citizen suit litigation strategy may favor easier victories over those
that would bring greater environmental benefit, and noting that the vast majority of CWA citizen suits are filed against
private industry, even though municipal facilities cause more pollution).
220 James R. May, Now More Than Ever: Trends in Environmental Citizen Suits, 10 WIDENER L. REV. 1, 5–10, 30
(2003); Adler, supra note 219, at 43.
221 Jeffrey G. Miller & Brooke S. Dorner, The Constitutionality of Citizen Suit Provisions in Federal Environmental
Statutes, 27 J. ENV’T L. & LITIG. 401, 454–55 (2012).
222 Stephen M. Johnson, Private Plaintiffs, Public Rights: Article II and Environmental Citizen Suits, 49 KAN. L. REV.
383, 399–402 (2001). See also Miller & Dorner, supra note 221; Robin Kundis Craig, Will Separation of Powers
Challenges “Take Care” of Environmental Citizen Suits? Article II, Injury-in-Fact, Private “Enforcers,” and Lessons
from Qui Tam Litigation, 72 U. COLO. L. REV. 93, 171 (2001).
223 See Friends of the Earth, 528 U.S. at 197 (Kennedy, J., concurring); id. at 209 (Scalia, J., dissenting).
224 For a concise history of the development of federal environmental crimes, see Joshua Ozymy & Melissa Jarrell
Ozymy, The Politics of the Criminal Enforcement of the U.S. Clean Air Act, 47 WM. & MARY ENV’T L. & POL’Y REV.
197, 201–03 (2022).
225 In re Winship, 397 U.S. 358, 364 (1970) (“Lest there remain any doubt about the constitutional stature of the
reasonable-doubt standard, we explicitly hold that the Due Process Clause protects the accused against conviction
except upon proof beyond a reasonable doubt of every fact necessary to constitute the crime with which he is
charged.”).
226 See Just. Manual, supra note 132, § 5-11.104.
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committed.227 For misdemeanors, grand jury involvement is not required and prosecutors may
commence a case by filing a charging document referred to as an information.228
A criminal violation consists of certain “elements,” meaning the different components of the
offense that the government must prove.229 Such elements in an environmental crime can include
an act (e.g., the defendant discharged a pollutant), a particular factual situation related to the
statutory requirement (e.g., the discharge is from a “point source” or to the “ambient air” or in
violation of a permit), a mental state (e.g., the defendant acted negligently, knowingly, or
willfully), a jurisdictional fact (e.g., the discharge was to a “water of the United States”), or a
result (e.g., a person was endangered).230

Types of Criminal Provisions in Environmental Laws
Much of the conduct that can result in civil penalties under the pollution statutes can give rise to
criminal liability as well, though as a general matter criminal penalties are reserved for offenses
committed with a certain degree of knowledge or intent.231 Broadly, environmental crimes under
the pollution statutes can arise from illegal discharges,232 false recordkeeping,233 failure to make
required reports,234 and tampering with equipment,235 among others.236 Examples of criminal
pollution control law offenses and penalties can be found in Table A-3. The statutes vary
structurally, but most include penalties for violating both statutory requirements and regulatory
requirements promulgated pursuant to statutory authority.237 Some statutes also impose criminal
227 See FED. R. CRIM. P. 7; Branzburg v. Hayes, 408 U.S. 665, 687 (1972); see also CRS Infographic IG10084,

Proceedings in Federal Criminal Cases: From Initiation to Indictment, by Cassandra J. Barnum (2025).
228 See Fed. R. Crim. P. 7, 58.
229 See 1 WAYNE R. LAFAVE, SUBSTANTIVE CRIMINAL LAW § 1.2(c) (3d ed. 2025) (“The totality of these various
items—conduct, mental fault, plus attendant circumstances and specified result when required by the definition of a
crime—may be said to constitute the ‘elements’ of the crime.”).
230 See 33 U.S.C. § 1319(c) (CWA discharges in violation of a permit); 42 U.S.C. § 7413(c)(4) (CAA negligent release
of hazardous substance resulting in endangerment).
231 See “The Mens Rea Requirement,” infra; see also Joseph Brennan et. al., Environmental Crimes, 62 AM. CRIM. L.
REV. 563, 566 n.15 (2025) (noting “overlapping civil, criminal, and administrative penalties” in FIFRA, TSCA, CWA,
RCRA, and CERCLA). EPA policies have articulated factors for determining whether to pursue a violation criminally
or civilly, including egregiousness, deceptive or misleading conduct, chronic noncompliance, and the need for
immediate injunctive relief. See, e.g., Memorandum from David M. Uhlmann, Assistant Adm’r, OECA to EPA Reg’l
Couns. & Deputies et al., Strategic Civil-Criminal Enforcement Policy, at 6 (Apr. 17, 2024), https://www.epa.gov/
system/files/documents/2024-04/strategic-civil-criminal-enforcement-policy-april-2024.pdf [https://perma.cc/UWP6PBTZ]; see also Just. Manual, supra note 132, § 5-11.1112 (noting parallel civil and criminal proceedings may be
appropriate “when in the course of a civil case the government receives evidence of deliberate violations of the law
meriting criminal prosecution or when a criminal investigation uncovers evidence of an on-going violation causing
environmental contamination that should be stopped quickly through an injunctive action”).
232 See, e.g., 33 U.S.C. § 1319(c) (CWA).
233 See, e.g., 42 U.S.C. § 7413(c)(2)(A) (CAA).
234 See, e.g., 42 U.S.C. § 9603(b) (CERCLA).
235 See, e.g., 42 U.S.C. § 7413(c)(2)(C) (CAA).
236 See Table A-3.
237 See, e.g., 42 U.S.C. § 7413(c)(1) (prohibiting knowing violation of various CAA statutory requirements, “including
a requirement of any rule, order, waiver, or permit promulgated or approved under such sections or subchapters”).
These requirements can be very specific, such as the work practice standard in CAA regulations requiring wetting of
asbestos-containing materials during renovation, 40 C.F.R. § 61.145(c)(3), or very broad, such as the CAA imposition
on owners or operators of stationary sources of a “general duty” to “identify hazards which may result from such
releases using appropriate hazard assessment techniques, to design and maintain a safe facility taking such steps as are
necessary to prevent releases, and to minimize the consequences of accidental releases which do occur.” 42 U.S.C.
§ 7412(r)(1).
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penalties for violating any condition of a permit issued pursuant to the pertinent regulatory
regime.238 Certain offenses apply only to specific categories of people or employees,239 while
others apply to any person or organization.240
Violations of any particular statute can be part of a course of conduct that implicates multiple
laws.241 Acts that violate more than one law can sometimes be charged under each law violated.242

Title 18 Criminal Offenses
Other offenses in the criminal code can overlap with environmental crimes, and prosecutors often
charge defendants with violating environmental statutes as well as various, generally applicable
prohibitions codified in Title 18 of the U.S. Code.243 For example, falsifying a required discharge
monitoring report to conceal illegal discharges from regulatory agencies could constitute a
violation of the CWA, which prohibits knowingly making “any false material statement,
representation, or certification” in any document “filed or required to be maintained” under the
act.244 An initial offense is punishable by two years’ imprisonment (or four for a subsequent
offense).245 The same conduct could also potentially violate a number of prohibitions in Title 18,

238 See, e.g., 42 U.S.C. § 6928(d)(2)(B) (prohibiting treatment, storage, or disposal of hazardous waste “in knowing

violation of any material condition or requirement of such permit”).
239 For example, the CAA regulations governing the handling of asbestos apply to “the owner or operator of a
demolition or renovation activity.” 40 C.F.R. § 61.145(a). Only a person who meets that definition can be prosecuted
for violating those regulations under 42 U.S.C. § 7413(c). See United States v. Pearson, 274 F.3d 1225, 1231 (9th Cir.
2001) (articulating “substantial control” test to determine whether a person constitutes an owner or operator as “ability
to direct the manner in which work is performed and the authority to correct problems”). See also 7 U.S.C.
§ 136l(b)(1)(B) (under FIFRA, offense limited to “commercial” pesticide applicators or distributors); 42 U.S.C.
§ 9603(b) (under CERCLA, offense limited to “person in charge”).
240 See, e.g., 42 U.S.C. § 6928(d) (RCRA prohibitions apply to “any person”); 33 U.S.C. § 1319(c) (CWA prohibitions
apply to “any person”). Enforcement of environmental crimes against corporations is subject to the Department-wide
corporate enforcement policy adopted by DOJ in March 2026, which governs corporate prosecutions by all components
of the Department (with certain exceptions for the Antitrust Division). See DOJ, CORPORATE ENFORCEMENT AND
VOLUNTARY SELF-DISCLOSURE POLICY (2026), https://www.justice.gov/dag/media/1430731/dl?inline
[https://perma.cc/DJ28-HWWY]. That policy generally instructs prosecutors not to pursue criminal cases against
corporations that have “voluntarily self-disclosed misconduct,” “fully cooperated with the Department’s investigation,”
and “timely and appropriately remediated the misconduct,” unless certain “aggravating circumstances” exist. Id. at 2.
241 See Joshua Ozymy & Melissa Jarrell Ozymy, Exploring Charging and Sentencing Patterns in U.S. Clean Air Act
Criminal Prosecutions, 61 NAT. RES. J. 229, 235–37 (2021) (collecting data on cases charged under more than one
environmental statute).
242 Conduct can be charged as violating more than one law without being unconstitutionally multiplicitous as long as
each crime requires proof of at least one unique element. See Blockburger v. United States, 284 U.S. 299, 304 (1932)
(“The applicable rule is that, where the same act or transaction constitutes a violation of two distinct statutory
provisions, the test to be applied to determine whether there are two offenses or only one, is whether each provision
requires proof of a fact which the other does not.”).
243 See Ozymy & Ozymy, supra note 241, at 239, tbl. 2 (reporting that 21% of CAA cases from 1983 to 2019 include
false statement charges; 18% include conspiracy charges). One example of a case implicating multiple categories of
offenses was United States v. Moss, 872 F.3d 304, 305 (5th Cir. 2017) (“A fatal welding accident occurred on an
offshore oil platform in the Gulf of Mexico in November 2012. Three years after that incident, the government indicted
the owner and operator of the platform and several oil platform contractors, charging criminal violations of the Outer
Continental Shelf Lands Act (OCSLA), 43 U.S.C. §§ 1331, et seq., and the Clean Water Act, 33 U.S.C. §§ 1251 et seq.,
as well as involuntary manslaughter. 18 U.S.C. § 1112.”).
244 33 U.S.C. § 1319(c)(4).
245 Id.
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including the general false statement statute and several obstruction-of-justice provisions, all of
which carry higher penalties.246
The false report could also, if more than one person were involved, violate 18 U.S.C. § 371,
which prohibits conspiracies to commit any offense against the United States, as well as
conspiracies to “defraud the United States, or any agency thereof

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Source: Frix Law Library, https://www.frixlaw.com/law-library/documents/crs%3AR48926. Public record. Not legal advice.