Rescheduling Marijuana & DOT Drug Testing: Key Risks Explained

What Rescheduling Means for Safety-Sensitive Employees

The Federal Government has not yet officially rescheduled marijuana, but both the current and previous administrations have considered moving it from Schedule I to Schedule III. While such a change could have significant economic impacts across industries, the most immediate and direct effects would be felt by employees in safety-sensitive positions regulated by the Department of Transportation (DOT). Even though Congress would still need to approve the change, rescheduling marijuana raises major concerns about how the DOT tests, regulates, and ensures the safety of its workforce.

HHS Testing Changes

The Department of Health and Human Services (HHS) sets the testing guidelines for all federal employees, which the DOT must follow for safety-sensitive positions. At present, the mandatory five-panel drug test screens for marijuana, cocaine, amphetamines, opiates/opioids, and PCP. If marijuana is moved from Schedule I to Schedule III, HHS would no longer require testing for it—and the DOT would also have to stop testing immediately.

Significant Labwork and Communication Challenges

An immediate change would cause major confusion as thousands of existing test requests and forms still list marijuana as part of the panel. Labs would need to redesign forms, panels, and testing protocols. Testing labs would need to redesign forms and panels, while Medical Review Officers (MROs) and Designated Employer Representatives (DERs) might still process outdated tests. This could lead to employees being wrongly flagged as positive for marijuana, despite it no longer being a tested substance.

Reasonable Cause Concerns

DOT testing for marijuana exists for an important reason: employees impaired by cannabis may struggle to focus, creating dangerous conditions when operating heavy machinery. If marijuana were no longer part of DOT testing, employers could not send visibly impaired workers for a reasonable-cause test under federal guidelines. At best, employers may stop the worker or require a non-DOT test, but it would not result in a federal violation creating a major safety gap.

ADA Protections

Today, 40 states and Washington, D.C. permit medical marijuana under specific conditions. A major distinction between Schedule I and Schedule III substances is that Schedule III drugs are recognized as having accepted medical uses. Rescheduling would formally recognize marijuana as having medical use, granting protections under the Americans with Disabilities Act (ADA). This protection would make it difficult for employers to discipline or terminate workers who test positive for THC on a urine screen—further complicating DOT enforcement.