Hollis said budget cuts had forced police to "prioritise" resources towards tackling organised criminal networks rather than individuals carrying drugs for personal use. He also backed calls for the current drug classification system into class A, B and C to be re-examined following concerns that bracketing substances such as heroin and ecstasy in the same class is confusing."

In some of the rats, the drug apparently lowered inflammation in the hippocampus -- the region of the brain responsible for short-term memory. It also seems to have stimulated the generation of new brain cells.

The following story discusses each candidate's stated position on medical marijuana.

Ever since California voters became the first in the nation to legalize medical marijuana in 1996, the state has faced unyielding opposition from the federal government, which insists it has the power to prohibit a drug it considers useless and dangerous.

That could all change with the next presidential election.

As the candidates prepare for a May 20 primary in Oregon, one of 12 states with a California-style law, Sen. Barack Obama of Illinois has become an increasingly firm advocate of ending federal intervention and letting states make their own rules when it comes to medical marijuana.

His Democratic rival, Sen. Hillary Rodham Clinton of New York, is less explicit, recently softening a pledge she made early in the campaign to halt federal raids in states with medical marijuana laws. But she has expressed none of the hostility that marked the response of her husband's administration to California's initiative, Proposition 215.

Police Search festival goers for drugs during Nimbin's Mardi Grass Festival.

A POLICE clampdown on cannabis smokers at Nimbin's annual Mardi Grass festival was allowing it to be taken over by amphetamine and alcohol use, an organiser said.

"The crowd are complaining there's not enough pot," Mardi Grass parade marshall Graeme Dunstan said of this weekend's festival.

"There's too much alcohol and too much speed, which people bring in from outside. The police go for cannabis because it's easy to spot."

Police have vowed to stamp out drugs in Nimbin. They sent officers from the riot, drug and mounted squads, plus regular officers, as an estimated 20,000 people gathered for a weekend of music, pot smoking and protest to demand the legalisation of cannabis.

"We are seeking to eliminate the supply of prohibited drugs," Richmond Local Area Command acting Superintendent Steve Clarke said on Friday. "We will not tolerate any breaches of any laws."

Michael Balderstone, president of the Nimbin Hemp Embassy, said the Nimbin community was furious about the police's approach. "You may as well get a stick and poke it in a hornet's nest. It's pointless. You can put us in jail for 20 years and you won't change our opinions."