Schedule III didn’t change a thing for truckers. A new USDOT memo confirms that safety-sensitive transportation workers still can’t use marijuana, and a state medical card won’t save your drug test.
If you drive a truck, fly a plane, or operate a bus for a living, the federal rescheduling of marijuana changed nothing for you. The U.S. Department of Transportation made that explicit in a memo this month: marijuana is still off-limits for safety-sensitive workers, and no amount of state-issued paperwork will get you out of a failed drug test.
The clarification comes after the April 23 order from the Justice Department and the DEA that moved FDA-approved cannabis pharmaceuticals and state-licensed medical marijuana products from Schedule I to Schedule III. That order did not legalize marijuana federally, and according to the new USDOT guidance, it did nothing to the testing rules that govern the federally regulated transportation industry under 49 CFR Part 40.
“Marijuana use is not compatible with safety-sensitive functions.”
U.S. Department of Transportation
A medical card won’t help you
The memo zeroes in on a specific question: if a driver tests positive and says it was a state-licensed medical product, can a Medical Review Officer flip that result to “negative”? The answer is a flat no.
The reasoning is technical but airtight. Even after rescheduling, state-dispensed marijuana isn’t an FDA-approved drug, and without FDA approval, a controlled substance can’t be prescribed. No prescription means no “legitimate medical explanation” under the rules, which is the only thing that could justify a positive result.
What won’t save your drug test
- A state-issued medical marijuana card
- A physician’s recommendation or certification
- Dispensary records or receipts
- The fact that marijuana is now Schedule III
Per USDOT, none of these meet the bar for a “legitimate medical explanation” under 49 CFR § 40.137(a).
USDOT spelled it out directly: a card, a doctor’s note, a receipt from a licensed dispensary, none of it clears the bar.
“Marijuana use under State marijuana programs or other non-prescription sources do not qualify as a ‘legitimate medical explanation’ under 49 CFR § 40.137(a).”
USDOT memo, updated May 15, 2026
The takeaway for the roughly 3.5 million commercial drivers and the pilots, bus operators and other safety-sensitive workers covered by federal testing rules is simple. Schedule III moved the needle on research and on certain pharmaceuticals. It did not move the needle at the wheel. For now, the only cannabis that clears a DOT test is the kind that comes with an FDA stamp and a prescription, and state-licensed medical weed is neither.
