If they are decriminalising (not legalising) it will still be illegal to smoke, posess and produce. Th egovernment can'ttax it until it is fully legit and production is under control.
Decrim is is the worst of 2 worlds. It's still illegal, you can still get busted for it, it's just the police prolly wont unless you are really flaunting it. Also the cash stays in the hands of the black marketeers.
Decrim is de facto policy in most UK cities, although smoking it in pubs, restaurants etc is not ok. Some clubs, however, turn a blind eye. Standing at the bus stop smoking a spliff, however, is not unusual.
It realy needs to be fully legalised so that the powers that be can slap a luxury tax on it (and still undercut the black market by 50%) and sell it through licenced vendors (such as liquor stores).
Prohibition of any kind of mind altering drug is never any more successful than American Alcohol Prohibition.
Prohibition is the most dangerous thing about most drugs, not the effects of the drugs themselves.
Prohibition is a violation of a human right to be the master of what goes on inside you. There are plenty of laws to prevent anti-social behaviour. If drug users are antiscoial, use those laws. Anti drug legislation is simply not necessary.