Charles Schuster, a psychologist at the US National Institute on Drug Abuse, near Washington, said the experience of American states that had partly decriminalised cannabis was that the number of users did not rise.
'It should be considered that decriminalisation - not legalisation - of small quantities of marijuana may be a rational social policy,' Dr Schuster said yesterday in London, where he is attending a conference on drug addiction at the Wellcome Centre for Medical Science.
'It prevents otherwise non-deviant people from being put into jail and mixing with people who are deviants.'
Although Dr Schuster is in favour of decrimininalising the use of cannabis, he is firmly against the legalised sale and distribution of the drug. Pushers should still be prosecuted if they possess large quantities that cannot be for personal use, he said.
'Legalisation is different. We don't need to offer people another form of intoxification. I'm not in favour of increasing marijuana use, but of lessening the social harm it can cause.'
Dr Schuster said that even in a society where cannabis is decriminalised he would hope that there would still be a strong stigma attached to its use. 'Why continue to smoke a weed that makes you forgetful, that makes you laugh at things that aren't very funny and that at best gives you an appetite for sweets?'
He welcomed the publicity generated in Britain over the Liberal Democrats' motion to decriminalise cannabis because of the potential for keeping otherwise law-abiding citizens out of prisons. 'But we should not tolerate someone being intoxified with cannabis behind the wheel of a car or at work.' These offences should be covered by separate legislation, he said.
Alcohol and cannabis differed in that it was possible to have one or two drinks without suffering the intoxifying consequences.Reuse content