A steady stream of customers filed into the Love Shack, where anybody with a city-issued cannabis card could buy $5 pot brownies or spend up to 20 minutes inhaling premium marijuana that sells for $320 an ounce.

It was business as usual at the medical marijuana club — one of dozens in San Francisco — even after the Supreme Court (search) ruled Monday that people who smoke pot for medicinal purposes can be prosecuted for violating federal drug laws.

Crime fighters in California and other states with medical marijuana laws insisted they were not about to start looking for reasons to shut down the dispensaries. But Dwion Gates, who was sitting next to a pair of bongs, said he's "a little bit shaken."

Click here to read the decision (FindLaw).

"I'm hoping that San Francisco will continue to be the compassionate place it has been in allowing places like this to exist legally," said Gates, 48, who smokes pot regularly to treat the pain from a bullet lodged in his back since 1983.

The ruling does not strike down medical marijuana laws in California, Alaska, Colorado, Hawaii, Maine, Montana, Nevada, Oregon, Vermont or Washington state. And state and local authorities in most of those states said they have no interest in arresting people who smoke pot because their doctors recommend it to ease pain. (Arizona also has a law on the books allowing medical marijuana, but no active program.)

Oregon, where more than 10,000 residents hold medical marijuana cards, stopped issuing new cards on Monday, but elsewhere officials assured the public the situation was status quo.

"People shouldn't panic. There aren't going to be many changes," California Attorney General Bill Lockyer (search) said. "Nothing is different today than it was two days ago, in terms of real world impact."

It remains to be seen whether the Drug Enforcement Administration (search) will crack down on medical marijuana users. The Justice Department didn't comment Monday.

Paul Armentano of the National Organization for the Reform of Marijuana Laws (search) said arrests of ailing patients have been rare, but the government has arrested more than 60 people in medical marijuana raids since September 2001.

Most of those arrests have been in California — the first state to allow medical marijuana, in 1996. On Monday, Gov. Arnold Schwarzenegger (search), who has previously supported use of pot by sick people, said only: "It is now up to Congress to provide clarity."

In Montana, the 119 residents who paid $200 to get on the state's confidential registry won't face state prosecution, said state Attorney General Mike McGrath. He said the state is not obligated to help federal authorities prosecute people following state law.

While the Supreme Court justices expressed sympathy for two seriously ill California women who brought the case, the majority agreed that federal agents may arrest even sick people who use the drug as well as the people who grow pot for them.

Dana May, of Aurora, Colo., said he will probably stop smoking pot because of the ruling, even though marijuana eases the debilitating pain of a nerve disease. "It'll change my entire world," he said. "I'm afraid they'll come after me."

Other patients said they were determined to continue smoking.

"I don't care whether it's legal or illegal," said cancer patient Christopher Campbell, 58, of Portland, Ore. Campbell suffers from lymphoma and has had his spleen removed, along with portions of his pancreas and stomach.

The ruling makes Valerie Corral (search) nervous. She operates a 150-plant pot farm in California's Santa Cruz County, providing marijuana for free to about 165 seriously ill members. Corral said the high court's decision "leaves us protecting ourselves from a government that should be protecting us."