In another step in their drive for legitimacy, medical-marijuana workers in Oakland, Calif., have joined a local chapter of the United Food and Commercial Workers Union. “Medical cannabis industry workers” at a half-dozen sites — including the prominent Oaksterdam University — have voted to join the Retail, Statewide Agriculture, Food Processing and Community Patient Care Union, UFCW Local 5.

The 100 medical-marijuana workers join a local whose membership currently tops 30,000. Unlike most employers, managers of the cannabis collectives welcomed unionization, largely for its public-relations value.