OK, we don’t ban the sale of alcohol but that is not a reason to encourage the sale of marijuana. Another study has come out saying what common sense and casual empiricism should render obvious without argument: The terrible truth about cannabis: Expert’s devastating 20-year study finally demolishes claims that smoking pot is harmless.

One in six teenagers who regularly smoke the drug become dependent on it,

Cannabis doubles the risk of developing psychotic disorders, including schizophrenia,

Cannabis users do worse at school,

Heavy use in adolescence appears to impair intellectual development,

One in ten adults who regularly smoke the drug become dependent on it and those who use it are more likely to go on to use harder drugs,

Driving after smoking cannabis doubles the risk of a car crash, a risk which increases substantially if the driver has also had a drink,

Smoking it while pregnant reduces the baby’s birth weight.

It ruins their own lives, the lives of the people around them, total strangers are harmed because of the additional car crashes they cause and their own children are not as robust. And the pluses are . . . you get to do your own thing while others have to pick the pieces up.