Last updated : May 12, 2025
Verifying a medical marijuana authorization needs to be part of your drug-free policy if it’s not already. The main reason being that failing to do so could lead to legal issues down the road.
Thirty-eight states and the District of Columbia allow medical marijuana use, however, the medical conditions warranting its use differ from state to state. Meanwhile, those who support legalization keep the pressure on employers to remove marijuana from company drug tests completely. So far, legalization doesn’t affect how employers handle positive drug test results—if you have all dotted all the “i’s” and crossed all the “t’s,” that is.
Hands off in some cases
There are instances when employees testing positive because of medical marijuana use are protected. For example, Nevada and New York ban employers from including marijuana on pre-employment drug tests entirely. However, both left carve-outs to continue testing for occupations where safety is an issue. That was a good idea because the federal government mandates drug testing of the safety-sensitive workforce.
However, it’s important to mention that the federal government is strongly considering changing marijuana’s drug classification from Schedule 1 to Schedule 3. The Drug Enforcement Agency defines Schedule 3 drugs as follows: substances, or chemicals defined as drugs with a moderate to low potential for physical and psychological dependence.
If this happens, the DOT may be required to remove marijuana from its drug test at the federal level. It’s good to know that a safety carve-out amendment can solve that issue.
Know the law
Employers that don’t utilize an MRO need to be aware of any existing marijuana laws in their state that pertain to employee drug tests. A positive result on a pre-employment drug test almost always allows the employer to withdraw the offer. Marijuana, however—as is the case in New York, for example—may now be an exception to the rule.
Conversely, some states handle drug testing hired employees differently than pre-employment tests. For example, Vermont and Minnesota block an employer from terminating someone the first time they fail a drug test if the employee agrees to complete a rehabilitation program. Other states require employers to relay all positive drug test results to test subjects within a certain period of time. Moreover, some states require employers to give employees time to contest the result and take a confirmation test.
Employers, look over your drug-free workplace policies. Make any necessary changes to keep you abreast of marijuana legalization within your state and document them in writing. Hiring a third party administrator (TPA) specializing in marijuana legalization can ensure that you comply. However, ultimately it’s the employer’s responsibility to ascertain that the drug testing laws in your state are followed so go over your procedures with a fine-toothed comb.
Mandated rules and regulations
Employers of the safety-sensitive workforce use a federally licensed Medical Review Officer (MRO). Currently, the DOT doesn’t consider state-authorized medical marijuana use to be a valid reason for a positive test result.
If a safety-sensitive employee tests positive for marijuana on a drug test, the laboratory notifies the Medical Review Officer (MRO). The MRO reviews the report and contacts the employee to discuss the test results. The employee supplies any medical evidence that contributes to the positive test result.
Marijuana is classified as an illegal drug with no medical purpose. Therefore, MROs commonly disregarded medical marijuana authorization at the state level as a valid excuse to combat a positive drug test result. However, the MRO community recognizes the growing number of positive test results and how it’s impacting employers. Some of them are choosing to reconsider their approach to the situation. DOT-regulated employers should check with their TPA (Third Party Service Associate) to see whether or not they accept state-issued medical marijuana authorization as a valid excuse for testing positive on a drug test.
What if they don’t
If the MRO doesn’t include verification of state-issued medical marijuana authorizations in their policy, employers shoulder greater responsibility.
The burden of proof to determine that the person is legitimately a medical marijuana patient rests with the test subject or the employer.
The employer should follow these steps:
- Ask the test subject to produce a state-issued medical marijuana card.
- Require the test subject to produce a copy of the physician’s Written Certification submitted to the state.
- Contact the physician who issued the authorization to verify its validity.
Many state laws are being argued in state court between employers and employees. Some states have employer protection for a Drug-Free Workplace, while others have sided with the employees’ right to use medical marijuana. As an employer, you must decide where you stand regarding marijuana use and have a well-written policy communicating your position.
Stand firm
Many employers feel they’re on shaky ground regarding marijuana legalization and employee drug testing. Drug-free policies are tricky enough to maneuver in the rapidly changing world of marijuana legalization, but they pose an even greater problem for employers that operate in multiple states. Creating a uniform company drug testing policy seems impossible for employers transporting goods cross-country. The driver’s responsibility to adhere to drug-free policies could go right out the window if passing through a state that legalizes recreational use.
Employers of both the safety-sensitive and general workforces should take a firm stance regarding marijuana drug testing because they do it for the sake of safety. Until the STATES Act passes, employers unquestionably reserve the right to keep marijuana on the test panel. They can stand with the Federal Government even if marijuana is legal at the state level—even if the state legalized medical marijuana.
The answer to the question
If the DOT regulates your company, MROs review medical marijuana authorizations. Moreover, some employers of the general workforce hire MROs as well. If not DOT-mandated, drug-free policies should include the steps taken when employees test positive for marijuana but have medical authorization at the state level.
An employer who is concerned about where marijuana legalization is leading their company regarding drug testing employees needs to speak up. Contact your state and federal officials and share your thoughts.
Alcohol in the workplace is strictly forbidden even though it’s a legal drug. Using medical marijuana or CBD products containing high levels of THC and testing positive for marijuana is a serious issue. Marijuana use impairs thinking and motor skills. Employees who use marijuana for medical purposes aren’t immune to its effects. We are responsible for keeping all of our employees safe at work.
Many employers feel that states are putting the marijuana cart before the horse. Until there is a test for current impairment, even if someone has proof to back up a state-authorized medical marijuana claim they can’t prove they weren’t impaired at the time of the test. Of course, neither can the employer. For the moment, it seems we’re caught up in a catch-22.
Studies show that breath detection coincides with the amount of time someone is affected by THC. Several companies are in the process of testing marijuana breathalyzers. Hopefully, they will hit the market soon—when perfected, this device should sell like hotcakes.
In the meantime, consider hiring a TPA who specializes in state marijuana laws and have them review your drug-free policies. They will advise you on any necessary changes that need to be made.
