The four lawsuits come in response to a plan to increase enforcement announced last month by U.S. attorneys in the state's four judicial districts by targeting dispensary operators and growers who were violating state law, which forbids for-profit sales, the Los Angeles Times reported.
Matt Kumin, one of the attorneys who filed the lawsuits, said the plaintiffs planned to ask judges Tuesday for temporary restraining orders that would halt the crackdown.
"The government has gone well down the road to allowing medical cannabis in the United States," Kumin said. "It can't reverse itself now, particularly because of the promises it made to the American people and the federal judiciary. They're stuck."
The 13-page suits argue the federal government's threat to prosecute owners of medical marijuana dispensaries and their landlords conflicts with the government's agreement not to use federal resources against medical marijuana patients who comply with state law.
"You tell people, 'Hey, you can do this,' and they rely on it, and the next thing you know, they can get arrested. It's entrapment," said Kumin, a San Francisco lawyer.
The lawsuits were filed against U.S. Attorney General Eric Holder, Drug Enforcement Administration head Michele Leonhart and each of the four federal prosecutors.
Thom Mrozek, a spokesman for Los Angeles U.S. Attorney Andre Birotte Jr. and the U.S. Justice Department, declined to comment on the lawsuits.