Leading up to the 2020 general election, thirty-four states (34) had legalized marijuana for medical use and an additional ten (10) states had legalized the drug for recreational use. While the federal government has chosen not to enforce federal law in states that have legalized the drug, marijuana remains an illegal Schedule I drug under the Controlled Substance Act due to its high potential for abuse, and the federal government does not budge on treating marijuana as an illegal drug for purposes of oversight, distribution, federal disability law, etc. Numerous states, however, provided employees with job protection for marijuana use. Thus, marijuana inhabits an "in-between zone" of legality that employers must navigate: it is legal and illegal at the same time.

We have received a number of inquiries regarding whether it is permissible to test (and take adverse actions based on positive results) for the main psychoactive component of marijuana-tetrahydrocannabinol (THC)-in pre-employment drug screens, post-accident drug screens, and in random drug screens; the answer is "it depends." If the job applicant and/or employee is applying for or works in a safety-sensitive position, was involved in a workplace accident, or will be performing/performs federal contractor work, then yes, employers may test for THC and take adverse actions based on a positive test result. If, however, an applicant is not subject to any one of those conditions, then the answer is a little more complicated. Let us explain.

First, when someone tests positive for THC there is no way of telling whether the person was impaired during the test, 30 minutes before the test, or 30 days before the test, as it is nearly impossible to assess a marijuana user's level of impairment. Unlike with alcohol, there is no per se level of marijuana measurable in the blood/urine that establishes a point of intoxication. THC metabolizes quickly into a compound that can remain in a user's body for weeks after an individual consumes marijuana and studies have shown that there is no correlation between the level of THC and impairment. Thus, high levels of THC can be detected when a person is impaired or well after an employee is no longer significantly impaired.

Second, many state medical marijuana laws (such as, Arizona, Arkansas, Connecticut, Delaware, Illinois, Maine, Minnesota, Nevada, New York, Oklahoma, Pennsylvania, and Rhode Island) contain anti-discrimination provisions that provide job protections for medical marijuana users. These provisions may require employers to (1) accommodate medical marijuana users, and/or (2) show impairment, which a positive drug test alone does not provide, as the basis for employment discipline or termination. Thus, while employers are free to test for THC, employers must ensure they are compliant with their state laws before taking any adverse actions based on a positive test result for applicants and/or employees prescribed medical marijuana for an eligible reason (eligibility depends on state).

What are other employers doing?

Employer reaction in states where marijuana has become legal (medical or otherwise) varies. Many employers are abandoning pre-employment testing for THC and are excluding it from random drug testing for positions that are not safety-sensitive. Other employers are not modifying their pre-existing zero tolerance drug policies nor considering employing any applicant testing positive for THC. Note that the use and possession of marijuana in Texas is still illegal; thus, Texas employers are not required to accommodate or otherwise permit the use of marijuana inside or outside of the workplace.


Some employers may wonder where does OSHA stand on this issue, as drug use on the job is an obvious safety hazard. To date, OSHA has not promulgated a standard requiring a drug-free workplace for most private employers, nor is there any significant guidance from OSHA on the issue of testing an employee for impairment from marijuana. Although neither OSHA nor state-plan states address drug-testing for THC, OSHA has recently stated that it does not prohibit post-incident drug testing, so long as the employer does not act to penalize or retaliate against an employee for reporting a work-related injury or illness, rather than for the legitimate purpose of promoting workplace safety and health.

Bottom Line

The bottom line is that random and post accident drug-testing programs for safety sensitive and federal contract work are permissible. But taking adverse employment actions based on a positive result for THC for other applicants or employees may run afoul with state-specific anti-discrimination laws. As such, employers should avoid making any quick decisions and instead speak with a lawyer about relevant state laws before setting policy and testing rules, or taking adverse employment actions.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.