Employers Beware: The Gray Areas in Medical Marijuana Testing

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Medical marijuana has been legalized in more than a dozen states and is being debated in additional state legislatures nationwide. As a result, organizations are becoming exposed to an increasing number of employees and contingent workers that could be under the influence or using medical marijuana while on the job, putting the safety of the staff, customers and public at risk.

Organizations face further challenges in addressing medical marijuana in their drug-free workplace policies and how to adequately monitor and test for it.

In states where it has been legalized, a patient, typically someone who suffers from chronic pain or serious illness, can obtain a physician’s recommendation to use medical marijuana. However, there is minimal oversight or monitoring of the patient’s consumption habits after they receive the recommendation, including impairment while on the job.

To mitigate the safety and legal risks of medical marijuana in the workplace, employers should develop a comprehensive drug-free workplace policy that addresses any gray areas regarding employee’s use of medical marijuana and impairment while on the job.

The limits of marijuana testing
A breathalyzer tests for blood alcohol levels and can determine if an individual consumed alcohol recently, how much they consumed and how impaired they were at the time of testing. In a workers’ compensation case or an employment lawsuit, this information can be vital to protecting an employer.

Unfortunately, predominant marijuana tests do not provide the same level of detail or accuracy as a breathalyzer. Based on testing alone, it is difficult for an employer to know if an employee who uses medical marijuana is impaired while on the job.

3 common marijuana testing methods
The three most common methods for drug testing marijuana usage are urine, hair and saliva testing. While these tests can indicate whether an employee tested positive for marijuana, they can only provide a window of time in which the marijuana entered the system and cannot accurately determine the current level of impairment.

1. Urine
A urine specimen can detect traces of marijuana metabolite anywhere from two hours to seven days in the past. Due to this window of time, urine specimens cannot tell an employer whether an employee was impaired on the job or was using the drug outside of work. Although urine specimens do reveal a level or amount of marijuana metabolite, this level can vary greatly due to environmental and lifestyle factors or the strength of the marijuana used.

2. Hair
Hair specimens can reveal long-term or chronic use of marijuana, but will not likely reveal one-time or sporadic use. Like the urine test, a hair test cannot determine exactly when a person used marijuana or their level of impairment. For these reasons, a hair test cannot conclusively say whether an employee is impaired on the job.

3. Saliva
A saliva test has a 24-hour period of detection—the most exact window of the three tests. When an employee tests positive for marijuana via oral fluids, it is likely that they used the drug within the last day. Even with this narrow window of use, there is still a gray area as to whether the usage impaired the employee while on the job.

Implications for employers
If you cannot determine whether a medical marijuana user is impaired on the job, how do you protect your company against safety and liability issues?

Due to such gray areas in testing, some employers decide to prohibit marijuana use company-wide. Other employers may decide to prohibit the use of medical marijuana for positions that are more safety-focused, while allowing medical marijuana use for positions with little safety risk.

In all cases, employers should proactively develop a medical marijuana policy in accordance with state law and their own unique safety needs. For organizations that are regulated by the Department of Transportation, employers should ensure that their drug testing policies are compliant with industry regulations.

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The HireRight Blog is provided for informational purposes only. It is not intended to be comprehensive, and is not a substitute for and should not be construed as legal advice. HireRight does not warrant any statements in the HireRight Blog. Any statutes or laws cited herein should be read in their entirety. You should direct to your own experienced legal counsel questions involving your organization’s compliance with or interpretation or application of laws or regulations and any additional legal requirements that may apply.