Dame Judi Dench, Sir Richard Branson and Sting are backing a campaign which urges David Cameron to decriminalise the possession of all drugs, but the move has been branded as “naïve” by critics.
The high-profile celebrities were among the signatories of an open letter to the Prime Minister criticising current drugs policy.
The letter, which was also signed by former Home Office Minister Bob Ainsworth, demands a “swift and transparent” review of drugs laws, followed by “immediate decriminalisation” if the review found laws had failed.
But Mary Brett, a trustee of charity Cannabis Skunk Sense said: “This is naïve in the extreme. These people have never read the literature on the harms drugs such as cannabis can do.
“There is no doubt that cannabis can cause psychosis, and skunk users are even more likely to become psychotic as a result. The message decriminalising drugs sends out is that they are safe.”
And a spokesman for the Home Office said: “We have no intention of liberalising our drugs laws.
“Drugs are illegal because they are harmful – they destroy lives and cause untold misery to families and communities.
“Those caught in the cycle of dependency must be supported to live drug-free lives, but giving people a green light to possess drugs through decriminalisation is clearly not the answer.”
The open letter, which was published in today’s Guardian by the campaign group Release, concludes: “The failure of the current UK system of criminalisation is clear – alternatives must be considered.
“It is time for the UK to review its policy, to reduce its reliance on an overburdened criminal justice system, and to adopt an evidence based and health focused approach to drug use.”
The letter was signed by 40 people including celebrities, lawyers, academics, artists and former police chiefs.
In 2004 the Government sparked a storm of protest by downgrading cannabis from a class B drug to a class C.
The policy proved to be a disaster and the Government was forced to revert cannabis to class B.