To liberalise or prohibit, that is the question. Prohibitionists argue that legalising anything increases its consumption. The world has enough of a problem with legal drugs like alcohol and tobacco, so why add to the problem by legalising cannabis, cocaine and heroinThe liberalisers say prohibition doesn’t work. By declaring certain drugs illegal we haven’t reduced consumption or solved any problem. Instead we’ve created an epidemic of crime, illness, failed states and money laundering.Who's right and who's wrongRussell Brand, Richard Branson, Julian Assange, Bernard Kouchner, Louise Arbour, Colombian President Juan Manuel Santos, former President of Brazil Fernando Cardoso, former President of Mexico and Member of the Club de Madrid Vicente Fox were among the speakers that took part in this debate in London in March 2012, with some speakers on stage and others beamed in from all over the World via Google+ Hangouts.