By Steve Doughty PUBLISHED: 5 October 2017
Cannabis users are more likely to commit violent crime, pioneering research has shown.
It warned those who smoke the drug regularly run an increased risk of using violence against others.
The project is the first to demonstrate that cannabis is not only linked with violent crime but is the cause.
Violent incidents monitored by the study based on the lives of more than 1,100 American psychiatric patients included assaults, attacks with weapons and rapes.
Researchers said that cannabis causes violence and they found no evidence that the link is the other way round – i.e. that violent people are more likely to use cannabis.
There was no support, they added, for theories put forward by campaigners anxious to free the drug from the taint of links with crime. The academics said the effect of cannabis use was clear and not diminished by other factors such as patients who were heavy drinkers of alcohol.
The study comes after a series of American states have decriminalised cannabis – despite it being stronger and more potent than the hash smoked by hippies in the Sixties – or made it available for medical use.