Source: Thomas P. Gies and Glenn D. Grant, Employee Relations Law Journal, Vol. 41 no. 1, Summer 2015
From the abstract:
Almost half of the states have enacted laws decriminalizing the use of marijuana for medical purposes. Eight of these jurisdictions provide some form of employment law protection for medical marijuana patients with registration cards confirming a treating physician’s prescription. Four states and D.C. allow the recreational use of marijuana and about 30 states have some type of “lawful conduct” or “lawful product” statute, some of which arguably apply to lawful uses of marijuana under state law. Yet the use of marijuana remains a crime under the federal Controlled Substances Act. Companies that maintain drug and alcohol programs, particularly those including zero tolerance drug testing protocols, face increasing uncertainty as a result of these developments. The authors of this article discuss the issue and note that the potential conflicts between state and federal law, combined with the existence of several open legal issues, may cause some companies to reconsider their substance abuse policies.