Companies struggle to understand changing state laws on marijuana and related workplace policies. Despite the federal ban, states are making their own laws on usage. Currently, recreational use of cannabis is legal in 21 states along with Washington, D.C., and Guam. Additionally, medical marijuana programs are sanctioned in 37 states, plus D.C., Guam, the Northern Mariana Islands, Puerto Rico and the Virgin Islands. In the November elections, residents of Maryland and Missouri voted to legalize recreational marijuana. Voters in Arkansas, North Dakota and South Dakota rejected legalization proposals. Despite growing public acceptance of marijuana, employers have latitude on how to approach the issue. Most state laws give businesses the ability to maintain a drug-free workplace and prohibit the consumption of cannabis while at work, says co-chair of the Cannabis practice in San Francisco Jennifer Fisher to SHRM.