As more states legalize the use of marijuana for medical or recreational purposes, employers in states such as North Carolina and South Carolina that have not relaxed their cannabis laws are asking under what circumstances they should send employees for testing based on suspicion of marijuana use at work. In certain circumstances, such as post-accident testing, the results of such tests can be used to limit or disqualify employees from receiving Workers’ Compensation benefits. The test results may also help clarify general liability or Occupational Safety and Health Administration (OSHA) compliance issues associated with an accident.

What about the more frequent situations where an employer simply suspects an employee of being under the influence of marijuana during working hours? Must the employer send the employee for a drug test in order to take action? In most cases, the answer is no. Unlike alcohol, marijuana tests do not reliably determine whether the employee is under the influence at work. They simply detect whether the employee has used marijuana in the recent past.

Employers do not necessarily need to drug test employees to take action under their policies and procedures. If managers trained in reasonable suspicion procedures provide documented and confirmed observations of marijuana use at work, the company can take adverse action without sending the employee for a test. Even if the observation is later challenged as erroneous, this possible mistake does not provide direct grounds for a legal claim against the employer.

Enforcement of the employer’s drug and alcohol policy should be consistent, meaning that employees who exhibit similar behaviors should be treated in a similar manner. Employers have the option of using drug tests to confirm their observations, but as stated above, a positive drug test may not be an indication that the employee was under the influence of marijuana at work.