Gordon Brown signalled a tougher approach to “soft” drugs yesterday with a surprise announcement of the second review in two years of the classification of cannabis.

Concern has been raised over the increased use of more potent “skunk” forms of the drug. There have been fears that its use is linked to psychotic illness, depression and suicide among young people.

It is the second time in a week that the Prime Minister has revealed plans to reverse policies of Tony Blair’s Government. Last week Mr Brown effectively abandoned plans for a supercasino in Manchester and it is understood that the Home Office became aware of the proposed review of cannabis classification only in the past two days.

Next week, Jacqui Smith, the Home Secretary, will publish a consultation paper on the next steps for the Government’s drug strategy, focusing on education and enforcement.

Mr Brown told MPs at Prime Minister’s Questions: “As part of the consultation, and the Cabinet discussed this yesterday, the Home Secretary will also consult on whether it is now right that cannabis should be moved from Class C to Class B.”

The Home Office said that it would ask the Advisory Council on the Misuse of Drugs (ACMD) to review the classification. A spokesman added: “It would be wrong to prejudge that review, which shows how seriously we take our priority of reducing drug-related harm.”

Cannabis was a Class B drug until it was downgraded in January 2004 by David Blunkett, the former Home Secretary. In January 2005, Charles Clarke, then the Home Secretary, asked the ACMD to review the downgrading decision. The committee recommended that the original decision to downgrade cannabis to a Class C drug should not be reversed.

The council said at the time that smoking cannabis may worsen asthma and damage the respiratory tract and that its use during pregnancy produced adverse effects on the child. It added that cannabis use may worsen the symptoms of schizophrenia and lead to a relapse in some patients. But it said: “For individuals, the current evidence suggests, at worst, that using cannabis increases the lifetime risk of developing schizophrenia by 1 per cent.”

It added: “The evidence for the existence of an association between frequency of cannabis use and the development of psychosis is, on the available evidence, weak.

“In the last year, over three million people appear to have used cannabis but very few will ever develop this distressing and disabling condition.

“And many people who develop schizophrenia have never consumed cannabis. Based on the available data the use of cannabis makes (at worst) only a small contribution to an individual’s risk for developing schizophrenia.”

In December 2005, the council reported that a slow decline in cannabis use had been sustained after reclassification and that there was “no evidence” of any short-term increase in consumption among young people.

In March, Vernon Coaker, the Home Office Minister, said that the Government had “no intention of reviewing the drug classification system”. He said: “Our priority is harm reduction, and we focus on enforcement, education and treatment.”

But in April, scientists showed for the first time how cannabis users can become paranoid and lose their grip on reality. A study led by Professor Philip McGuire, at the Institute of Psychiatry in London, looked at 15 male volunteers who were not regular users of cannabis.

It revealed that the drug’s most powerful active ingredient, tetrahydrocannabinol (THC), reduced activity in a part of the brain that helped to keep people sane. Brain scans carried out on the group showed that THC dampened down activity in the interior frontal cortex, which acted as a check on irrational thoughts and prevented inappropriate behaviour.

Mr Blunkett said in a statement that he was “quite relaxed” about the prospect of a review of his decision to downgrade the drug. The statement said: “It is worth reflecting that cannabis use amongst young people has fallen and the campaign to educate and inform young people has been the most successful government information programme in recent years.”

David Davis, the Shadow Home Secretary, said: “We have long called for the reclassification of cannabis based on the science and evidence available.” Tim Hollis, the chairman of the Association of Chief Police Officers drugs committee and the Chief Constable of Humberside, said: “We welcome a well-informed debate.”

Drug penalties

–– As a Class C drug, the maximum penalty for possession of cannabis is two years, an unlimited fine or both. Dealing in a Class C drug can lead to 14 years in prison, an unlimited fine or both

–– A young offender in possession of cannabis can receive a police reprimand, final warning or be charged, depending on the seriousness of the offence

–– It is unlikely that adults caught in possession of cannabis will be arrested. Most offences of possession result in a warning and confiscation of the drug, but they can be prosecuted if it is a repeat offence

–– Possession of a Class B drug can lead to five years in jail, an unlimited fine or both

–– Dealing in Class B drugs can lead to up to 14 years in prison, an unlimited fine or both

*Source: Times database

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