Legislative Scheduling of Controlled Substances
July 9, 2024
Legislative Scheduling of Controlled Substances
The Controlled Substances Act (CSA) regulates drugs and
• Pub. L. No. 99–570, Title I, § 1867, 100 Stat. 3207,
other substances deemed to pose a risk of abuse and
3207–55 (1986) (minor amendment to Schedule II(a)(4),
dependence. Drugs become subject to the CSA by being
which applies to cocaine and other coca leaf derivatives)
placed in one of five lists, known as Schedules I-V. A lower
schedule number corresponds to greater restrictions, so
• Pub. L. No. 99–646, § 84, 100 Stat. 3592, 3619–20
substances in Schedule I are subject to the strictest controls,
(1986) (further minor amendment to Schedule II(a)(4),
while substances in Schedule V are subject to the least
which applies to cocaine and other coca leaf derivatives)
strict. There are two ways in which substances can be
scheduled under the CSA: Congress can schedule
• Pub. L. No. 101–647, Title XIX, § 1902(a), 104 Stat.
substances by enacting legislation, or the Attorney General
4789, 4851–52 (1990) (adding anabolic steroids to
(in conjunction with the U.S. Department of Health and
Schedule III)
Human Services, or HHS) can schedule substances via an
administrative process laid out in the CSA. The Attorney
• Pub. L. No. 108–358, § 2, 118 Stat. 1661, 1661–63
General generally delegates CSA scheduling authority to
(2004) (amending 21 U.S.C. § 802 to define “anabolic
the Drug Enforcement Administration (DEA).
steroid” to include multiple specified chemicals)
This In Focus surveys instances in which Congress has
• Pub. L. No. 112–144, Title XI, § 1152, 126 Stat. 993,
scheduled a controlled substance or changed the status of a
1130–32 (2012) (adding “cannabimimetic agents” and
controlled substance under the CSA via legislation. It also
certain other substances to Schedule I)
briefly discusses considerations for Congress related to
legislative scheduling. For more information about the CSA
• Pub. L. No. 115–334, Title XII, § 12619(b), 132 Stat.
and scheduling procedures under the Act, see CRS Report
4490, 5018 (2018) (removing low-THC “hemp” from
R45948, The Controlled Substances Act (CSA): A Legal
the CSA definition of “marijuana” and amending
Overview for the 118th Congress, by Joanna R. Lampe.
Schedule I to exclude “tetrahydrocannabinols in hemp”)
Legislative Scheduling Actions
Congress has also enacted legislation that did not directly
Congress placed numerous substances in Schedules I-V
add substances to the statutory schedules but instead
when it enacted the CSA in 1970. The schedules of
required the Attorney General to schedule specific
substances controlled by legislation are codified at 21
substances:
U.S.C. § 812. Since the CSA’s enactment, most subsequent
scheduling changes have been made by DEA via the
• Pub. L. No. 95–633, Title I, § 102(c), 92 Stat. 3768,
rulemaking process, but Congress has at times enacted
3772 (1978) (directing the Attorney General to place
legislation to schedule controlled substances or change the
pipradrol and SPA in Schedule IV to comply with the
status of existing controlled substances.
United States’ obligations under the Convention on
Psychotropic Substances of 1971)
CRS searched for instances of legislative scheduling,
rescheduling, and descheduling by reviewing the
• Pub. L. No. 106–172, § 3(a), 114 Stat. 7, 8–9 (2000)
amendment history of 21 U.S.C. § 812 and cross-checking
(directing the Attorney General to schedule gamma
it against DEA’s list of scheduling actions. Through that
hydroxybutyric acid [GHB] and providing that, if the
process, CRS identified the following examples of
Attorney General failed to do so within a specified time
legislative scheduling actions:
period, GHB “(together with its salts, isomers, and salts
of isomers) is deemed to be scheduled”)
• Pub. L. No. 91–513, Title II, § 202, 84 Stat. 1236, 1247–
52 (1970) (original enactment of the CSA, establishing
Temporary Scheduling of Fentanyl-Related
the schedules of controlled substances and placing a
Substances
number of substances in each schedule)
In addition to the permanent legislative scheduling actions
listed above, Congress has also enacted legislation to
• Pub. L. No. 98–473, Title II, § 507(c), 98 Stat. 1837,
temporarily control a class of substances known as
2071 (1984) (amending Schedule II(a)(4), which already
“fentanyl-related substances” (FRS).
applied to “coca leaves” to include application to
“cocaine and ecgonine and their salts, isomers,
When a substance is scheduled under the CSA, it usually
derivatives, and salts of isomers and derivatives”)
remains in the same schedule unless Congress or DEA
moves it to a different schedule or removes it from control.
However, the CSA grants DEA the authority to place a
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Legislative Scheduling of Controlled Substances
substance in Schedule I temporarily when “necessary to
instance, compared to administrative scheduling, legislative
avoid an imminent hazard to the public safety.” Pursuant to
scheduling may offer greater speed and flexibility.
that authority, DEA initially imposed temporary controls on
Administrative scheduling under the CSA proceeds via
FRS in February 2018 via an administrative temporary
formal rulemaking, which generally takes months or years
scheduling order (Fentanyl TSO). The Fentanyl TSO
to complete. In making scheduling decisions, DEA is
applied to a broad class of FRS that meet specific criteria
required by statute to make certain findings with respect to
related to their chemical structure. DEA did not initiate
each substance’s potential for abuse and accepted medical
permanent scheduling of the class of FRS, likely because
use. DEA scheduling orders (other than temporary
the class includes thousands of chemicals, and the effects,
scheduling orders) are subject to judicial review, including
potential for abuse and dependence, and medical utility of
consideration of whether the agency properly applied the
many of those substances are unknown. The agency has
relevant statutory standards.
continued to take administrative scheduling actions with
respect to specific fentanyl analogues, including selected
By contrast, Congress is not bound by the CSA’s
FRS subject to the Fentanyl TSO.
substantive or procedural requirements. This means that it
can schedule a substance immediately, regardless of
On February 6, 2020, Congress enacted the Temporary
whether the substance meets the statutory criteria. While
Reauthorization and Study of the Emergency Scheduling of
scheduling legislation may also be challenged in court, the
Fentanyl Analogues Act, Pub. L. No. 116–114, 134 Stat.
scope of judicial review of legislation is typically more
103, which temporarily extended the Fentanyl TSO until
limited than judicial review of regulations. Legislative
May 6, 2021. Congress has since extended the Fentanyl
scheduling may be the only way to permanently schedule
TSO several times. The most recent extension expires
large classes of substances, such as FRS, where it is not
December 31, 2024, see Pub. L. No. 117–328, div. O,
feasible for DEA to conduct the required statutory analysis
§ 601, 136 Stat. 4459, 5231 (2022). For additional
for all substances in the class. Congress might also
information on the temporary control of FRS, see the
schedule, reschedule, or deschedule a substance via
“Fentanyl Analogues” section of CRS Report R45948, The
legislation if it disagreed with DEA’s evaluation of the
Controlled Substances Act (CSA): A Legal Overview for the
substance.
118th Congress, by Joanna R. Lampe.
Relatedly, the CSA provides DEA with limited options for
Considerations for Congress
regulating controlled substances. The CSA established
Congress designed the CSA to delegate scheduling
Schedules I-V, with each schedule carrying a defined set of
decisions to agencies with relevant expertise and has often
regulatory controls and penalties for unauthorized activities.
deferred to DEA on scheduling controlled substances. The
If DEA decides to control a substance under the CSA, it
CSA rulemaking process involves input from HHS on
must place the substance in one of the existing schedules.
scientific and medical matters, an opportunity for interested
The agency has asserted some authority to tailor controls to
parties to comment on proposed regulations, and a final
specific substances, but it cannot create new schedules or
decision on the record by DEA, subject to possible judicial
implement regulations or exceptions from control that are
review. As noted above, since the enactment of the CSA,
not authorized under the CSA. If Congress wishes to
most scheduling actions have been taken by DEA through
regulate a controlled substance in a way that does not fit
that administrative rulemaking process.
within the existing CSA framework, or allow DEA to do so,
it must enact legislation.
Congress has broad authority to amend the CSA, including
by scheduling, rescheduling, or descheduling substances. In
The CSA also directs DEA to control substances as
recent years, some Members of Congress have introduced
required pursuant to the United States’ international treaty
legislation that would change the status under the CSA of
obligations. While those obligations may limit DEA’s
substances including marijuana (currently in Schedule I—
discretion to relax controls over certain substances, U.S.
the Department of Justice and DEA have proposed to move
treaty commitments do not prevent Congress from
it to Schedule III), FRS (temporarily in Schedule I), and
exercising its constitutional authority to enact new laws,
xylazine (an animal sedative that is regulated by the U.S.
even when doing so might cause the United States to violate
Food and Drug Administration and not currently controlled
its treaty obligations.
under the CSA).
Joanna R. Lampe, Legislative Attorney
There are several reasons why Congress might decide to
schedule or reschedule substances via legislation. For
IF12709
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Legislative Scheduling of Controlled Substances
Disclaimer
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