Construction Law: Drug Laws

Medical Marijuana Use & Drug Testing

by Trent Cotney, partner, Adams & Reese, LLP


(Editor’s Note: Trent Cotney, partner at Adams & Reese, LLP, is dedicated to representing the roofing and construction industries. Cotney is General Counsel for the Western States Roofing Contractors Association and several other industry associations. For more information, contact the author at (866) 303-5868 or go to


Depending on what state you live in, your company may be challenged by all of the recent changes in drug laws. Although marijuana is still illegal according to federal law, many states have legalized it for recreational and medical use. That atmosphere makes enforcing a drug-free workplace more difficult.

Over the years, opinions about cannabis use have changed. Marijuana has become more acceptable, and law enforcement has become more lenient. However, employers in many industries cannot afford to have their employees under the influence at work, yet they are seeing a rise in positive drug tests. According to one testing vendor, positive drug tests rose last year from 3.6% in 2020 to 3.9%. That is an increase of 8.3%, making the positivity rate the highest in 20 years.

Many companies are alarmed by that increase, but they are also facing staffing shortages. So they are hesitant to use drug tests as part of their pre-employment screening process. If they still use drug tests, many are opting to drop THC, marijuana’s psychoactive component, from the drug panel.

As employers wrestle with the issues, there are some good reasons for continuing with drug testing. Among these are ensuring the safety of the worksite and the employees, reducing on-the-job injuries, lowering health insurance premiums, keeping employees and customers safe, and improving productivity. Drug tests also help identify employees who are struggling with addiction and can encourage them to get professional help. However, drug testing has its downsides as well. For example, employees may claim disability discrimination or complain of privacy breaches. In addition, they may be subject to false positives or false negatives, which can make the testing process either contentious or ineffective. Employers may also have a hard time recruiting if testing is a requirement.

In the past, you could easily have a zero-tolerance drug policy. But in states where medical and personal use is allowed, it is difficult to hold that hard line. This is especially true if you have employees with medical conditions that can be treated with cannabis. Therefore, it is essential that you communicate with them. Take the time to work with your employees who qualify for medical marijuana and see what accommodations you can make. While you may want them to get the relief they need, you do not want them impaired at the workplace.

In addition, remember that some states protect recreational marijuana use for off-duty workers. Nevada has banned hiring decisions based on pre-employment cannabis testing. If your employees have safety-sensitive roles, which include handling hazardous materials, operating machinery, and carrying a weapon, you may have the right to insist on drug testing. But be sure to check your local laws.

Another approach to consider is to drop all pre-employment drug testing. Instead, you could focus only on testing based on reasonable suspicion. Such an approach allows you to address workers suspected of worksite drug use rather than having a blanket requirement for everyone. But managers would have to be trained to spot behaviors that can indicate drug use. These include, but are not limited to, slurred speech, drowsiness, and red eyes. However, you must use caution since many other issues could cause such symptoms. If those symptoms are chronic, be sure to document them before insisting on a drug test.

In the current atmosphere of drug tolerance, your approach to drug testing can probably not be one size fits all. Instead, your company leadership should work with your HR department to create drug-testing policies that address your workers’ individual needs and considerations. Encourage your employees to talk to their supervisors or HR about any issues that warrant medical marijuana use, then make every effort to accommodate them. But also make it clear to all employees that being impaired on the worksite is not acceptable. It is a safety risk to them, their fellow workers, customers, and the company.

If you are unsure of your state laws and how they affect you, do not hesitate to seek legal advice. An experienced employment attorney can explain your local laws, discuss your concerns, and help you navigate your situation.