The medical marijuana shop next to a tattoo parlor on a busy street in Los Angeles looks much like hundreds of other pot dispensaries that dot the city. Except for one thing: on the glass door — under a green cross signalling that cannabis can be bought there for medical purposes — is a sticker for the United Food and Commercial Workers union (UFCW), the largest retail union in the US.

The dispensary, the Venice Beach Care Centre, is one of three medical marijuana dispensaries in Los Angeles that are staffed by dues-paying union members. Another 49 in the city plan to enter labour agreements with the UFCW this year, the union says.

Together, the dispensaries are a symbol of the growing bond between the nascent medical marijuana industry and struggling labour unions.

During the past few years unions, led by the UFCW, have played an increasingly significant role in campaigns to allow medical marijuana, now legal in California, 17 other states and Washington, DC.

In the November elections, UFCW operatives also helped get-out-the-vote efforts in Colorado, where voters approved a measure that made possession of one ounce (28.3g) or less of the drug legal for anyone 21 and older. Washington state approved a similar measure and both states require regulation of marijuana growers, processors and retailers.

Union officials acknowledge that their support stems partly from the idea that the marijuana industry could create hundreds of thousands of members at a time when overall union membership is shrinking.

The US Bureau of Labour Statistics reported last month that union members — who accounted for 11.8% of the workforce in 2011 — now make up about 11.3% of all American workers, the lowest percentage in nearly a century.

Retail unions such as the UFCW are fighting the rise of part-time workers and a steady drop in real wages over the past two generations. Organised labour also has been under pressure from Republican governors such as Wisconsin’s Scott Walker, who led an effort to curb collective bargaining rights for public workers in that state.

Union officials say there are now 3000 UFCW members who work in the cannabis industry, a tiny fraction of the union’s 1.3-million members.

Article continues on page two: Obama won't pursue recreational users; marijuana to add billions of dollars to GDP and create a large number of jobs...