Q: If an employee tests positive for marijuana/marijuana metabolites on an
employment-related drug test, does that mean the employee is ‘impaired?’
- No, a positive workplace drug test alone does not equate to impairment. While
employment policies often prohibit employees from using drugs or being impaired at the
worksite or during work hours, there is currently no drug workforce test (excluding
alcohol tests measuring blood alcohol concentration) that can inform an employer as to
whether an employee is ‘impaired’ based on the concentration (level) of
drugs/metabolites present in a donor specimen. Some state laws explicitly address what
can and cannot be considered for determining whether an employee is ‘impaired’ by
marijuana, but most do not. Proper guidance and training of employees and supervisors
to recognize objective, observable behavior and other symptoms related to drug use are
critical for making impairment and reasonable suspicion drug testing determinations.
- Note: Only a handful of states have defined impairment due to marijuana use as it relates to
operating a motor vehicle and those levels in blood vary. Currently, there is no consensus on
what the standard of impairment is for marijuana.