Cannabis Campaign: Let cool heads decide

A House of Lords inquiry will look at the evidence, not the myths, reports Graham Ball

THE Independent on Sunday cannabis campaign won a major victory last week with the announcement that, for the first time, the use of the drug for medicinal as well as recreational purposes is to be the subject of a high-level parliamentary investigation.

Our campaign to decriminalise cannabis use in Britain has prompted a vigorous national debate. The Government has remained aloof. Now it will be forced to confront the facts, which are to be compiled and assessed by a sub-group of the influential House of Lords Science and Technology Select Committee.

"The decision to inquire into the scientific case for and against continuing to prohibit the medicinal and recreational uses of cannabis was taken because of the high level of interest in the subject in both houses and in light of the recent British Medical Association report," said a House of Lords spokesman.

Last November, the BMA rigorously examined all the scientific evidence supporting the use of cannabis to treat a growing list of ailments and concluded that, contrary to the 1971 Misuse of Drugs Act, it does have therapeutic properties.

The Lords sub-committee charged with investigating the wider use of cannabis is to be chaired by Lord Perry of Walton, a doctor, pharmacologist and former vice-chancellor of the Open University. He said: "The Select Committee chose the brief and have given me the job. We intend to begin hearing evidence next month." It is planned that the sub-committee hearings will begin at Easter and the full report will be ready in the autumn.

Lord Perry said: "When the report is compiled there will be a debate in the House of Lords and our findings will be made public. After the debate, the findings will be put to the Government and they will have to respond. A parliamentary inquiry has considerable powers."

Among those assisting the inquiry are Lord Porter of Luddenham, who won a Nobel Prize for chemistry, and Professor Heather Ashton, emeritus professor of clinical psychopharmacology at the University of Newcastle and author of the BMA study of the therapeutic potential of cannabis.

She said: "I believe that any investigation by Parliament will help raise the level of understanding among policymakers. In my experience it takes at least 20 years to get just one piece of information over to MPs.

"Personally, I have reservations about the use of cannabis in treating long-term illness and there are obvious problems to resolve concerning the use of the drug with the mentally ill and other vulnerable groups. I hope the Lords will also consider the psychological aspects and the specific question of increased tolerance among regular users. On the recreational side I have worries concerning traffic accidents and the effects on pilots."

Greg Poulter of the drugs charity Release believes the inquiry is a significant step. "I am delighted that their Lordships have had the courage to grasp the nettle of investigating the recreational aspects of cannabis as well as the medical. It will be hard for the Government to ignore this committee's findings and it may put an end to their head- in-the-sand attitude."

Important questions for their Lordships to consider are:

1) Is cannabis addictive?

Some scientists believe that long-term use leads to heavy dependency; others say this is rare and is not "true" addiction.

2) How quickly does the psychoactive (mind-altering) effect wear off?

This aspect is vitally important as the Government intends to introduce roadside cannabis testing. The tests are so sensitive that they can detect tiny quantities of the drug up to a month after it was smoked or ingested. But scientific tests have shown that, within a few hours, cannabis in brain cells falls below the concentration required for detectable psychoactivity.

3) Does it affect fertility?

Many who argue against decriminalisation say that cannabis use leads to diminished sperm-count in men and suppresses a hormone that women need to conceive. Most scientific studies have failed to find any evidence of this. In studies that have shown an impact, it is modest, temporary and of no apparent consequence for reproduction. Some tests on animals dosed with sustained and extremely high levels of THC, the psychoactive component of cannabis, have shown impaired fertility.

4) Does cannabis harm the brain?

Opponents of cannabis use the claim that it destroys brain cells. Their evidence is based on an early, controversial, study of brain damage to rhesus monkeys which had been exposed to six months of high-concentration cannabis smoke. Recent, more carefully conducted research found no evidence of brain abnormalities in monkeys exposed to the equivalent of four to five cannabis joints daily for a year.

5) Can it cause mental illness?

Many who work in mental health and welfare fear that cannabis is responsible for psychosis, especially among young people. But no convincing scientific evidence has been produced to show that even long-term use causes psychological damage.

6) Are cannabis smokers more likely to get lung cancer?

Some scientists argue that burning cannabis contains agents that can cause cancers of the mouth, neck and lung.

7) Does cannabis damage memory and the ability to learn?

It is accepted that cannabis users' short-term memory is affected. No evidence has yet been found that even long-term use permanently impairs memory or other cognitive functions.

8) Does cannabis use lead to hard drug abuse?

Statistical evidence does not support this. The majority of cannabis users never use another illegal drug.