HOWZAT

The ACMD recommended downgrading cannabis to a Class C drug as recently as January 2004, a move that proved controversial as some medical evidence then emerged linking cannabis use with mental illness, including schizophrenia.

The final decision to move the drug to Class C was taken by David Blunkett, who lost his job as Home Secretary not long after.

Anti-drugs campaigners complained that the change had sent out a mixed message, and that many young people were left believing that cannabis had been legalised. In fact, the only substantial change in the law was that the maximum penalty for cannabis possession fell from five years in prison to two years. The maximum sentence for dealing in the drug remained the same, at seven years.

Mr Blunkett's successor, Charles Clarke, promised before the 2005 general election that cannabis classification would be re-examined, but the advisory council reported back that there was no new evidence that would lead it to change its mind.

In July 2007 - another period when a general election seemed imminent - Mr Brown announced that he wanted the classification of cannabis to be reviewed once more. But he too has been rebuffed by the scientists, it appears.

The Home Office says there is real public concern about the potential mental health effects of cannabis use and, in particular, the use and availability of stronger kinds of cannabis such as skunk.

This morning Jacqui Smith, the Home Secretary, refused to be drawn into criticising the ACMD, telling BBC Radio 4’s Today programme that she would refrain from comment until she had seen its report.

“I haven’t seen the report; I don’t know what it says and I have this rule, which I think people would expect me to have, that I read things before I comment on them,” she said.

She did agree however that she supported the view of the Prime Minister that the status of cannabis should be reviewed.

“I do believe that cannabis use is serious which is why it’s illegal ... which is why we as a government have already taken action," said Ms Smith.

“For example, if you look around you will see adverts which make clear to young people that there is a link between cannabis use and mental health problems.

“I think the Prime Minister was right to ask the Advisory Committee whether or not we have got the classification right and I think I’m right to wait until I’ve seen the detail of what they’ve said before I comment on it.”

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