We're heading into a recession and there's no real way for the government to raise additional funds without raising taxes in the middle of a recession.
Labour are out regardless what they do, So why not legalise it now and reap the taxes, remove a large portion of street crime (which leads to drug dealing knife crime amongst poor teenagers) and make 20% of the population think Labour are cool enough to vote for again.
I've just got my girlfriend pregnant so won't be part taking in the smoke fest - but lets remove the money from crime and stick it into the country's coffers.
Alcohol is evidently making the streets a nightmare on a Friday / Saturday night.
It will kill a lot of birds with one stone