The federal agencies responsible for evaluating and scheduling controlled substances lack comprehensive written policies governing key parts of the process, according to a new government watchdog report released Wednesday as the Drug Enforcement Administration (DEA) continues considering the broader rescheduling of marijuana.

The U.S. Government Accountability Office (GAO) report, published September 23, found that although DEA’s recent scheduling decisions have consistently aligned with recommendations from the Department of Health and Human Services (HHS), both DEA and the Food and Drug Administration (FDA) have significant gaps in their formal procedures.

Under the Controlled Substances Act, DEA is responsible for making federal scheduling decisions. For certain actions, the agency must obtain a scientific and medical evaluation from HHS, which relies largely on an eight-factor analysis conducted by FDA.

GAO examined scheduling actions involving 208 substances between 2020 and 2025. DEA was required to consider an HHS scientific and medical evaluation and recommendation for 95 of those substances and did so in every case.

Of those 95, DEA had issued final scheduling decisions for 84 by the end of 2025. Every one of those 84 decisions aligned with HHS’s recommendation. The other 11 substances remained under extended temporary scheduling orders.

Despite that record, GAO found that DEA does not have written policies identifying internal roles, responsibilities and procedures for several major components of the scheduling process.

The watchdog said DEA doesn’t “have any policies or procedures regarding how its staff are to conduct evaluations or schedule substances.”

Those gaps include procedures for collecting and analyzing information before administrative rulemaking, handling new-drug scheduling, conducting three-factor analyses for temporary scheduling, performing eight-factor analyses used to determine schedule placement and considering HHS recommendations when making final decisions.

DEA officials told investigators that additional policies are unnecessary because the Controlled Substances Act and related regulations already establish the agency’s legal requirements. GAO disagreed, saying the law does not provide the level of detail needed to specify which personnel are responsible for particular tasks or exactly how those responsibilities should be carried out.

The watchdog said formal procedures could become particularly important if experienced agency personnel leave and institutional knowledge is lost.

FDA also has policies covering parts of the scheduling process, but GAO found it lacks comprehensive procedures explaining how staff should conduct eight-factor evaluations and develop scheduling recommendations.

One particularly significant issue involves the concept of a substance’s “potential for abuse,” a key consideration in determining where a drug belongs under the Controlled Substances Act.

GAO said federal law does not define the term, and FDA officials acknowledged that the absence of a written definition for “potential for abuse,” including what constitutes a “high potential for abuse,” has presented challenges when comparing substances and recommending schedules.

FDA’s Controlled Substance Staff instead relies partly on professional judgment and person-to-person training when performing the analyses. GAO recommended that FDA establish written criteria and procedures while preserving flexibility for substance-specific evaluations.

The report also found that an agreement governing coordination between FDA and the National Institute on Drug Abuse (NIDA) is more than 40 years old and references offices that no longer exist. FDA and NIDA officials agreed that the agreement should be updated.

The findings come as the federal government continues a closely watched proceeding over marijuana’s broader status under the Controlled Substances Act.

HHS recommended in August 2023 that marijuana be moved from Schedule I to Schedule III after applying a new two-part analysis for determining whether a substance has a currently accepted medical use.

GAO noted that a 2024 Department of Justice Office of Legal Counsel opinion subsequently concluded that HHS’s approach was legally sufficient and that DEA must give significant deference to HHS’s scientific and medical findings during the rulemaking process.

In April, Acting Attorney General Todd Blanche issued a separate final rule moving FDA-approved marijuana products and marijuana covered by state medical marijuana licenses to Schedule III. The government simultaneously continued proceedings over whether the remaining marijuana covered by federal law should also be transferred from Schedule I to Schedule III.

DEA held an 11-day hearing on that broader proposal from June 29 through July 15. The agency’s online docket continues to list the proceeding and its hearing transcripts.

GAO made three recommendations: that DEA develop comprehensive policies for evaluating and scheduling substances, that FDA establish procedures for its evaluations and scheduling recommendations, and that FDA and the National Institutes of Health update the decades-old agreement governing coordination with NIDA.

The Department of Justice, DEA, HHS, FDA and NIH agreed with the recommendations.