As long as their use of marijuana does not interfere with their ability to work, there is no need for concern. If someone is unable to perform competently, then management should focus on the issue of performance. Obviously, truck drivers and others with safety-sensitive jobs should be required to reveal any prescription medication that affects their ability to work. If employees state they are using medical marijuana, I imagine under the California Fair Employment and Housing Act you would be required to reasonably accommodate by perhaps giving them longer breaks, flexible working hours or part-time work schedules. One way in which I think marijuana should be treated differently is in use on company premises.
Employers usually allow employees to take their medication on site.
This is a difficult one for people who smoke marijuana, due to the issue of second-hand smoke. I think it is reasonable to ask people who smoke to do so away from the company premises, but I could be wrong on that. The publishers disclaim any liability, loss or risk incurred as a consequence, directly or indirectly, of the use and application of any of the contents of this information. This information is not a substitute for the advice of a competent legal or other professional person. All rights reserved.