DOT Holds Drug-Testing Line for Safety Workers After Rescheduling

The Trump administration’s move to shift state-regulated medical marijuana into a less-restricted federal category has not changed the rules for one of the largest groups of workers affected by federal drug policy. Truck drivers, airline pilots, railroad engineers, and other safety-sensitive transportation workers are still prohibited from using medical marijuana under federal transportation drug-testing requirements — and a positive test result will not be excused by a state-issued medical card, no matter what the federal schedule now says.

The Department of Transportation made that position explicit this month through its Office of Drug and Alcohol Policy and Compliance, issuing new Q&A guidance addressed to medical review officers — the licensed physicians who evaluate confirmed drug test results for covered workers. The question was direct: after the federal rescheduling order, can a medical review officer verify a marijuana-positive test as negative when the worker says the result came from a state-licensed medical marijuana product?

The answer is no. “Marijuana use is not compatible with safety-sensitive functions,” the agency said.

Why Rescheduling Doesn’t Flow Through

The gap between the rescheduling order and DOT’s drug-testing rules comes down to how federal law defines a valid prescription.

On April 23, 2026, the Justice Department and the Drug Enforcement Administration issued an order placing two categories of marijuana products in Schedule III of the federal controlled substances schedule: FDA-approved products containing marijuana, and marijuana products regulated under a qualifying state-issued medical license. Both categories shifted out of Schedule I — where they had been classified since 1970 as having no accepted medical use — and into a category that acknowledges medical value and carries lower federal controls.

But the rescheduling order didn’t make state-dispensed marijuana prescribable under federal law. DOT’s guidance explains the mechanism: even after rescheduling, marijuana dispensed through a state medical program still lacks FDA approval. Under federal drug law, a controlled substance can only be prescribed through channels the FDA has approved. Without that approval, it isn’t a legitimate prescription — and that matters enormously for how drug tests get reviewed.

DOT’s workplace testing framework, which covers workers in aviation, trucking, railroads, mass transit, pipelines, and other federally regulated transportation industries, allows for a positive test result to be verified as negative only when there is a “legitimate medical explanation” — defined as use of a legally prescribed controlled substance that complies with federal prescription requirements. A state medical marijuana card doesn’t satisfy that definition. Neither does a physician’s recommendation, a dispensary receipt, or any other document generated under a state medical program.

So the outcome for a covered worker who tests positive for cannabis metabolites is unchanged: the medical review officer verifies the result as a violation, the worker is removed from safety-sensitive duty, a return-to-duty process begins, and the violation is reported to the federal Clearinghouse that employers must query before allowing workers into safety-sensitive roles.

The Rest of the Federal Response Looks Different

DOT’s hard line stands out against what other federal agencies have done since the rescheduling order took effect.

The ATF has circulated a draft revision to its firearms-purchase form that drops prior language treating medical marijuana use as federally prohibited — an implicit acknowledgment that state-licensed medical marijuana is now federally permissible in contexts outside the transportation safety framework. The Treasury Department and IRS have signaled new tax guidance is forthcoming for the cannabis industry, acknowledging that the federal tax disallowance that had barred state-licensed medical cannabis businesses from deducting ordinary expenses no longer applies to those operators. The DEA, meanwhile, has opened an expedited registration pathway for state-licensed medical marijuana businesses to integrate into the federal controlled-substances framework.

A recent Congressional Research Service analysis of the rescheduling order’s scope concluded that certified patients who possess state-dispensed medical marijuana now hold certain protections under the new federal category, including what the report described as apparent authorization to possess marijuana for medical use. That’s a meaningful legal development for patients — but it operates in a different lane than occupational drug testing.

DOT’s reasoning is that its testing framework is a separate regulatory system, built on a requirement that any legitimate medical explanation involve an FDA-approved, federally prescribed drug. The rescheduling order didn’t alter that framework. It didn’t direct DOT to change anything, and DOT has issued no indication it plans to act on its own.

This position isn’t new — DOT has been consistent throughout the rescheduling process. When President Trump signed an executive order in December 2025 directing the Justice Department to complete the rescheduling process, DOT quickly posted an advisory reminding safety-sensitive workers that nothing had changed for them. The May 2026 guidance applies the same reasoning to the rescheduling order that followed. Transportation Secretary Sean Duffy has also made his personal view clear: he has called marijuana “really addictive” and warned that federal policy signals around cannabis send a “dangerous” message.

What would actually change the situation for covered workers is a DOT rulemaking — notice, comment, final rule — that amends the existing federal drug-testing framework to carve out a space for Schedule III medical marijuana. That process doesn’t follow automatically from the rescheduling order. It requires DOT to act independently, and DOT has signaled no interest in doing so.