S. 331: HALT Fentanyl Act
Sponsor
Bill Cassidy
Republican · LA
What S. 331 does
The HALT Fentanyl Act permanently places fentanyl-related substances, as a class, in schedule I of the Controlled Substances Act, the category for drugs with a high potential for abuse and no currently accepted medical value. Offenses involving them face the same quantity thresholds and penalties as fentanyl analogues, for example a 10-year mandatory minimum prison term for 100 grams or more.
The act also eases registration rules for controlled-substance research. It creates an alternative registration process for certain schedule I research, permits a single registration for related research sites in some cases, and lets a registered researcher carry out certain manufacturing activities with small quantities of a substance without a separate manufacturing registration. It also states Congress's agreement with the court's reading in United States v. McCray, that butyryl fentanyl can be treated as a fentanyl analogue.
How the House voted
Passed · June 12, 2025103 Democrats broke with their party to vote no
1 Republican broke with their party to vote no
On Passage: S 331 HALT Fentanyl Act · Roll no. 166 · Official record
How the Senate voted
Passed · March 14, 2025On Passage of the Bill S. 331 · Record vote 127 · Official record
S331 Legislative Journey
Signed into Law
Jul 16, 2025
Became Public Law No: 119-26.
+3 more actions this day
Action Taken
Jul 8, 2025
Presented to President.
House: Passed 321-104
Jun 12, 2025
On passage Passed by the Yeas and Nays: 321 - 104 (Roll no. 166). (text: 6/11/2025 CR H2625-2627)
+3 more actions this day
House: Vote Held
Jun 11, 2025
POSTPONED PROCEEDINGS - At the conclusion of debate on S. 331, the Chair put the question on passage of the bill and by voice vote, announced that the ayes had prevailed. Mr. Pallone demanded the yeas and nays and the Chair postponed further proceedings until a time to be announced.
House: Passed
Jun 10, 2025
Rule H. Res. 489 passed House.
House: Committee Action
Jun 9, 2025
Rules Committee Resolution H. Res. 489 Reported to House. Rule provides for consideration of H.R. 884, H.R. 2056, H.R. 2096 and S. 331. The resolution provides for consideration of H.R. 884, H.R. 2056, H.R. 2096, and S. 331 under a closed rule with one hour of general debate for each bill. The resolution provides for one motion to recommit on H.R. 884, H.R. 2056, and H.R. 2096, and one motion to commit on S. 331.
House: Action Taken
Mar 18, 2025
Held at the desk.
Senate: Action Taken
Mar 14, 2025
Passed/agreed to in Senate: On Passage of the Bill S. 331: Bill Passed 84 - 16 (Record Vote Number: 127).
About the Sponsor
Bill Cassidy
Republican, LA · 17 years in Congress
Committees: Health, Education, Labor, and Pensions, Veterans' Affairs, Finance
View full profile →
Cosponsors at time of passage (31)
This bill has 31 cosponsors: 6 Democrats, 24 Republicans, 1 Independent, reflecting bipartisan support. Cosponsors represent 24 states: Alaska, Alabama, Arizona, and 21 more.
Martin Heinrich
Democrat · NM
Chuck Grassley
Republican · IA
Roger Marshall
Republican · KS
Todd Young
Republican · IN
Steve Daines
Republican · MT
Mike Rounds
Republican · SD
Shelley Capito
Republican · WV
Eric Schmitt
Republican · MO
John Kennedy
Republican · LA
Ruben Gallego
Democrat · AZ
Maggie Hassan
Democrat · NH
Catherine Cortez Masto
Democrat · NV
Committee Sponsors
Judiciary Committee
10 of 21 committee members cosponsored at the time
What laws does S. 331 change?
5 changes
Sections Amended
Section 202(c) of Controlled Substances Act (21 U.S.C. 812(c))
adding at the end of schedule I the following: ``(e)(1) Unless specifically exempted or unless listed in another schedule, any material, compound, mixture, or preparation which contains any quantity of a fentanyl-related substance, or which contains the salts, isomers, and salts of isomers of a fentanyl-related substance whenever the existence of such salts, isomers, and salts of isomers is possible within the specific chemical designation
Section 302(c) of Controlled Substances Act (21 U.S.C. 822(c))
adding at the end the following: ``(4) An agent or employee of a research institution that is conducting research with a controlled substance if-- ``(A) the agent or employee is acting within the scope of the professional practice of the agent or employee; ``(B) another agent or employee of the institution is registered to conduct research with a controlled substance in the same schedule; ``(C) the researcher who is so registered-- ``(i) informs the Attorney General of the name, position title, and employing institution of the agent or employee who is not separately registered; ``(ii) authorizes that agent or employee to perform research under the registration of the registered researcher; and ``(iii) affirms that any act taken by that agent or employee involving a controlled substance shall be attributable to the registered researcher, as if the researcher had directly committed the act, for purposes of any proceeding under section 304(a) to suspend or revoke the registration of the registered researcher; and ``(D) the Attorney General does not, within 30 days of receiving the information, authorization, and affirmation described in subparagraph (C), refuse, for a reason listed in section 304(a), to allow the agent or employee to possess the substance without a separate registration
Section 302(e) of Controlled Substances Act (21 U.S.C. 822(e))
adding at the end the following: ``(4)(A) Notwithstanding paragraph (1), a person registered to conduct research with a controlled substance under section 303(g) may conduct the research under a single registration if-- ``(i) the research occurs exclusively on sites all of which are-- ``(I) within the same city or county; and ``(II) under the control of the same institution, organization, or agency; and ``(ii) before commencing the research, the researcher notifies the Attorney General of each site where-- ``(I) the research will be conducted; or ``(II) the controlled substance will be stored or administered
Section 302 of Controlled Substances Act (21 U.S.C. 822)
adding at the end the following: ``(h) Continuation of Research on Substances Newly Added to Schedule I
Section 102 of Controlled Substances Act (21 U.S.C. 802)
adding at the end the following: ``(60) The term `fentanyl-related substance' has the meaning given the term in subsection (e)(2) of schedule I of section 202(c)
S. 331 Quick Facts
- Committee
- Judiciary
- Chamber
- Senate
- Policy
- Crime and Law Enforcement
- Introduced
- Jan 30, 2025
Became Public Law No: 119-26.
Jul 16, 2025
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S. 331 Bill Text
“To amend the Controlled Substances Act with respect to the scheduling of fentanyl-related substances, and for other purposes.”
Source: U.S. Government Publishing Office
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