Arguing that some "top" scientific journals had published "horrific examples" of poor quality research on the alleged harm caused by some illicit drugs, the Imperial College professor called for a new way of classifying the harm caused by both legal and illegal drugs.
"Alcohol ranks as the fifth most harmful drug after heroin, cocaine, barbiturates and methadone. Tobacco is ranked ninth," he wrote in the paper from the centre for crime and justice studies at King's College, London, published yesterday.
"Cannabis, LSD and ecstasy, while harmful, are ranked lower at 11, 14 and 18 respectively."
Saucy stuff