Ask the Expert: Medical Marijuana and Workplace Safety

By Randy Clayton on Jan 17, 2019
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Ask the Expert: Medical Marijuana and Workplace Safety

Missouri Amendment 2 passed on Election Day 2018, legalizing the use of medical marijuana for qualifying patients, and making Missouri one of 33 states having passed legislation permitting its use. It’s likely employers won’t see their first employee or applicant with a medical marijuana prescription until late 2019 or early 2020, which leaves some much needed time to help clear the smoke on employer rights in the State of Missouri when it comes to medical marijuana in the workplace. In this Ask the Expert, our experienced Safety and Health Consultant, Randy Clayton, answers your questions about the effects of medical marijuana on workplace safety and productivity.

Does the Use of Marijuana Increase Workplace Injuries?

Safety is cited by employers as one of their top concerns when asked about use of medical marijuana by workers, and rightfully so. Especially with negative side effects like changes to the central nervous system including sensory perception, thought formation and expression, short-term memory, and impaired thinking and learning. In terms of physical effects, impaired motor performance, loss of balance and coordination, decreased ability to judge distance and space, sedation, and a slow reaction time may also be experienced. Not to mention hallucinations, anxiety and panic attacks.

Human Resources Suspected Drug and Alcohol Use at Work

According to Occupational Health and Safety, numerous studies have linked an increase in workplace injuries to marijuana use. In fact, one study by the American College of Occupational and Environmental Medicine found workers who tested positive for marijuana in pre-employment drug screens had 55 percent more industrial accidents, 85 percent more injuries and a 75 percent higher absentee rate than those who tested negative.

Further research into the effects of marijuana and safety have revealed cognitive impairment lasts beyond 24 hours post marijuana consumption. The 2013 flight simulator study on pilots concluded marijuana use has a negative effect on learning, memory, attention, reason and concentration. And these effects were present one, four and 24 hours after its use. Additionally, a 2016 meta-analysis of 21 studies in 13 countries with data on more than 200,000 participants found marijuana use to increase risk of motor vehicle crashes by 20 to 30 percent.

A prescription for medical marijuana does not give an employee the right to put their own safety or the safety of their co-workers at risk.


Jan 17 Randy Clayton LI

Can Employees Consume Medical Marijuana in the Workplace?

No. According to Fisher Phillips, Amendment 2 provides express language prohibiting public use of marijuana in any form, including smoking, ingesting or otherwise consuming marijuana including vapor form, edible, oil, etc. Your workplace policies should be updated accordingly.

Can I Maintain a Drug-Free Workplace?

Yes, Missouri employers can still maintain a drug-free workplace, even after you see those first medical marijuana prescription cards. Fisher Phillips goes on to state, “Amendment 2 provides a safety net for employers prohibiting employees from filing claims against Missouri businesses for wrongful discharge, discrimination, or similar actions based on the employer prohibiting the employee from being under the influence of marijuana while at work or disciplining the employee for working or attempting to work while under the influence of marijuana.”

It’s important to note, for Department of Transportation (DOT) employees, marijuana use is strictly prohibited both on and off the job. You can find out more about medical marijuana and DOT regulations in this Ask the Expert blog with Jeanette Coleman, Director of Human Resources.

Other workers exempt from state medical marijuana laws include federal contractors, who must strictly abide by the Federal Drug-Free Workplace Act, and employees in safety-sensitive positions must not be impaired by any illegal or legally prescribed substance while at work.

Find out five questions to ask when testing employees for marijuana.

Are Medical Marijuana Users Protected by the ADA?

No, medical marijuana users are not protected by the American with Disabilities Act (ADA). Because marijuana is still illegal under federal law, medical marijuana is not covered under the ADA, even if the state, Missouri, has legalized its use for medicinal purposes. To find out more about federal vs state law, medical marijuana and the ADA, read this blog.

A Final Note

A changing cultural attitude toward marijuana along with state law legalizing medicinal and recreational use may lead to the misperception about the drug’s safety in the workplace. However, a prescription for medical marijuana does not change the need for a safe and productive workplace.

Axcet HR Solutions can be your go-to source for questions about changing laws and employee safety.

Five Ways Employers Can Prepare for Medical Marijuana in the Workplace

No Legal Advice

The information and materials on this site are provided for informational purposes only. They do not necessarily represent the position or opinions of Axcet HR Solutions or its employees, and they do not constitute legal advice.  You should consult with a qualified lawyer of your choice who is familiar with all of the facts of your situation before making a decision about any legal matter.

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Written by Randy Clayton

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