Congressional Committee Directs DOT to Keep Testing Truck Drivers for Marijuana

Appropriations Language Preserves Drug-Testing Mandate

The House Appropriations Committee inserted directive language requiring DOT to maintain existing marijuana testing protocols for commercial drivers subject to Federal Motor Carrier Safety Administration (FMCSA) oversight. The provision appears in the committee report accompanying H.R. 4782, the Transportation, Housing and Urban Development, and Related Agencies Appropriations Act for fiscal year 2027. The panel advanced it on June 3.

DOT must disregard any changes to cannabis scheduling under the Controlled Substances Act when administering drug-testing requirements for safety-sensitive transportation workers. That's what the directive says. Committee staff confirmed the language applies specifically to drivers holding commercial driver's licenses (CDLs) operating vehicles over 26,001 pounds or transporting hazardous materials.

Rescheduling Doesn't Alter Federal Safety Standards

The Trump administration finalized cannabis rescheduling from Schedule I to Schedule III in May 2026, but the move didn't automatically change workplace safety regulations. DOT regulations at 49 CFR Part 40 govern drug and alcohol testing for approximately 12 million transportation workers, including:

• Commercial truck and bus drivers under FMCSA jurisdiction
• Pilots and air traffic controllers regulated by the Federal Aviation Administration
• Railroad engineers and conductors under Federal Railroad Administration oversight
• Transit operators subject to Federal Transit Administration rules

Current DOT testing protocols require pre-employment, random, post-accident, reasonable suspicion, and return-to-duty screening for THC metabolites. A confirmed positive test at 50 nanograms per milliliter triggers disqualification from safety-sensitive duties. No exceptions.

Committee Cites Highway Safety Concerns

Representative Tom Latham (R-IA), chair of the Transportation-HUD Subcommittee, stated the directive addresses concerns that rescheduling could create ambiguity in enforcement. A subcommittee aide said the language ensures DOT maintains a zero-tolerance policy for cannabis use among CDL holders regardless of state legalization laws or federal scheduling changes.

Here's the landscape: 24 states have enacted adult-use cannabis laws and 38 states permit medical marijuana, creating a patchwork of conflicting standards for interstate commercial drivers. The directive aims to preserve uniform federal safety standards across state lines.

Trucking Industry Backs Testing Continuation

The American Trucking Associations (ATA) and Owner-Operator Independent Drivers Association (OOIDA) both support maintaining existing marijuana testing requirements. ATA President Chris Spear said in a June 3 statement that the organization has consistently advocated for preserving DOT drug-testing protocols despite cannabis policy reforms.

Industry groups cite Federal Motor Carrier Safety Administration data showing that cannabis-related violations increased 32 percent from 2023 to 2025 among CDL holders. FMCSA's Drug and Alcohol Clearinghouse recorded 89,472 marijuana violations in 2025, up from 67,781 in 2023. That's a significant jump.

Appropriations Bill Advances to House Floor

The full Appropriations Committee approved H.R. 4782 on June 3 by a vote of 32 to 24, with the marijuana testing directive included in report language rather than bill text. Report language doesn't carry the force of law but signals congressional intent to executive agencies and often influences how regulations get implemented.

The bill allocates $26.4 billion for DOT in fiscal 2027, including $785 million for FMCSA operations. House leadership hasn't yet scheduled floor consideration. The Senate Appropriations Committee is expected to mark up its version of the transportation funding bill in late June.

Regulatory Uncertainty Remains for Other Workplaces

The directive applies only to DOT-regulated safety-sensitive positions and doesn't address workplace drug testing in other industries. Private employers not subject to federal transportation safety rules retain discretion to modify or eliminate marijuana testing policies in states with legalization laws.

The Department of Labor hasn't issued guidance on how Schedule III reclassification affects employer drug-testing programs outside DOT jurisdiction. Employment law attorneys note that cannabis remains federally prohibited for non-medical use regardless of scheduling, which means employers can maintain zero-tolerance policies if they choose.

For comprehensive background on federal cannabis workplace policy, see the CannIntel topic hub on drug testing and employment.

What happens next? House floor consideration of H.R. 4782, expected in late June. Senate action and conference committee negotiations will determine whether the directive language survives in final appropriations law.