A BOLTON MP has backed a group of leading scientists who have criticised plans to reclassify cannabis as a more dangerous drug.

In a letter to the Guardian newspaper, the signatories say it would be “very damaging” for the Government to ignore expert advice not to upgrade the drug.

Dr Brian Iddon, MP for Bolton South-east, has signed the letter, saying the Government’s U-turn could cause confusion among young people.

The Home Secretary wants to change cannabis from class C to class B, putting it on a par with amphetamines.

The letter says this would risk reversing the downward trend in the use of cannabis since it was reclassified as a class C drug in 2004.

It also says it would send confusing messages to the public about the more serious dangers of class B drugs.

Since it was downgraded there has been growing concern about the potential impact on mental health, particularly of stronger “skunk” varieties.

Despite these fears, in May, the Advisory Council on the Misuse of Drugs (ACMD) concluded in a Government-commissioned review that it should stay as class C.

The council said cannabis was not as dangerous as other class B substances and evidence suggested only a “probable, but weak, causal link between psychotic illness, including schizophrenia, and cannabis use”.

Home Secretary Jacqui Smith wants to overrule that recommendation, a move which was debated in the House of Lords yesterday.

Dr Iddon said: “If we have got the ACMD and they make the recommendation that cannabis should stay at class C because it’s not as dangerous as class B drugs then I think the Government has to stick with that.

“They are making a political judgement and ignoring scientific evidence.”

He added: “I think it could cause confusion among young people.”

The letter, whose signatories include two former chief scientists, Sir David King and Lord May, said that in pressing ahead with reclassification, “the Government has rejected the explicit advice of its appointed experts for the first time in nearly 30 years”.