At present, medical marijuana may be used legally in 33 states and D.C., and recreational marijuana in 11 states and D.C. Marijuana is illegal for any purpose in 17 states and remains illegal under federal law. Many employers deny prospective employees’ employment and fire current employees for marijuana use—whether or not their use is actually illegal—based on drug test results. For employers attempting to discourage illegal drug use, the use of marijuana drug test results to make employment decisions is problematic due to shortcomings in drug testing, making it nearly impossible to determine whether marijuana use was legal.
According to the annual Quest Diagnostics Drug Testing Index, the number of workers and job applicants who tested positive for marijuana climbed 10 percent from 2018 to 2019. Drug tests, however, are highly unreliable: one could fail a drug test even without the recent use of marijuana. Urine tests for marijuana metabolites can only show recent marijuana use, not intoxication or impairment. This is because of the time required between smoking and your body breaking down THC (tetrahydrocannabinol), the active ingredient of marijuana, to the metabolites that are eliminated in the urine. THC remains detectable in bodily fluids for up to 90 days after last use. Hence, the current technology to test marijuana levels does not reliably show if an individual is intoxicated or was intoxicated at work. As marijuana is legal in many states, an employer cannot tell—based solely on an employee’s having failed to a drug test—whether the marijuana use was lawful through a urine test. However, because many employers have a zero tolerance for drug use, most workplaces use urine tests for any recent use of drugs.
Fortunately, some states have changed their laws in recognition of the unreliability in marijuana testing. In Nevada, starting in 2020, employers cannot refuse to hire a job applicant for failing a marijuana test, with limited exceptions. Similarly, in New York City, many employers will no longer be able to test job applicants for marijuana or THC. The new mandate will take effect in 2020. In Arizona, Arkansas, Delaware, Minnesota, and Rhode Island, employers may not refuse to hire or otherwise penalize a person based solely upon the person’s status as a medical marijuana patient or for testing positive for marijuana on a drug test. However, the federal government, at present, does not limit the right of private companies to perform drug testing on their employees.