During the past year, there’s been a growing federal push to undercut medical marijuana laws in states including Washington, Montana, California and Colorado.

A key turning point was a June 2011 Justice Department memothat prosecutors have used as ammunition to shut down dispensaries or jack up licensing fees.

The memo and subsequent enforcement have made it difficult for the small businesses to stay afloat, say advocates of legalized marijuana.

“There has been pushback,” says Robert Corry, a Denver-based attorney who specializes in marijuana laws.

Corry is advising some dispensary owners to close shop and operate on a small scale privately, as allowed by state law. It’s not worth the fees and hassles, he says.

He says roughly 50 Colorado dispensaries have already closed this year.

In one case of marijuana law enforcement, federal authorities raided dozens of Montana marijuana dispensaries in March 2011. That state’s once-thriving community of medical dispensaries has virtually disappeared, despite voter-approved medical marijuana use in 2004.

Two Takes on a Memo

Momentum swung decidedly against marijuana laws last June, when the U.S. Department of Justice issued a memo on medical marijuana stating that cultivating and selling marijuana are activities that violate the Controlled Substances Act, regardless of state law.

“States thought as long as they’re following state law they were not going to be targeted. But that hasn’t been the case,” says Morgan Fox, a spokesman for the Marijuana Policy Project.

Instead, the Drug Enforcement Administration and U.S. Attorney's office interpreted the Cole memo (named after the author James Cole, a deputy attorney general) as an open season to target medical marijuana dispensaries, advocates say.

Pushback From Colorado to Montana