Why legalising cannabis is safer than decriminalising it

I hate weed. Week after week, I see the tragic effects of this substance and how it destroys the minds of the young. I work on a mental health ward which, like many around the country, is home to some of the victims of our current lackadaisical attitude towards cannabis. This drug is particularly dangerous to the developing brains of young people and yet we know that this age group are the most likely to be experimenting with it. Despite protestations from the powerful pro–cannabis lobby, it has been proved beyond doubt that cannabis use is associated with depression, anxiety, psychosis and avolition (poor motivation).

A third of psychosis cases in London are the result of smoking skunk, according to extensive research conducted by Sir Robin Murray, a professor of Psychiatric Research at the Institute of Psychiatry, King’s College London, and an expert in drug-induced psychosis. Another study by Oxford University has shown that weed increases the risk of depression in teenagers by 40 per cent. These studies join hundreds of others which show that, far from being the harmless, benign substance campaigners would have us believe, cannabis is a dangerous, damaging intoxicant that has a profound effect on the structure and function of the brain.

Despite all this evidence, Sadiq Khan, the mayor of London, is planning a radical new approach to drugs in the coming months. Instead of prosecution, under-25s in certain boroughs will be offered courses on drug use. He is, in effect, decriminalising cannabis in the capital. In many ways, weed already is decriminalised: London’s streets are filled with its pungent stench. But Khan’s approach is an enormous gamble with the mental health of the capital.