The Government is facing mass resignations from the official advisory body on drugs after the sacking of its chairman, The Times has learnt.

Two members of the Advisory Council on the Misuse of Drugs quit yesterday in protest at Alan Johnson’s dismissal of David Nutt in a row over the relative harm caused by drugs and alcohol.

Les King, an expert chemist, was the first to resign. He said that the Home Secretary had denied Professor Nutt his right to free speech and called for the council to become truly independent of politicians. He was swiftly followed by Marion Walker, a pharmacist and clinical director with the substance misuse service at the Berkshire Healthcare NHS Foundation Trust.

The affair has led scientists to question the Government’s wider commitment to the independence of external scientific advisers, and raised fears that experts will become reluctant to sit on advisory panels.

Scientists on the council are preparing a letter to ministers seeking assurances that they will remain free to set their agenda and to speak freely about their research and findings. It is possible the 28 remaining members will quit if their concerns are not addressed before a council meeting next week.

One of the country’s leading experts on drug dependence said that, without such assurances, it would be difficult for any scientist to succeed Professor Nutt as council chairman while retaining the respect of their peers.

In a letter to The Times, Ian Stolerman, Emeritus Professor of Behavioural Pharmacology at King’s College London, said: “All scientists who work without pay to advise the Government must surely be considering their positions. After this unjustified dismissal, anyone who takes over from Professor Nutt risks being branded by the scientific community as a collaborator with a Government that has no respect for expertise.”

Lord Drayson, the Science and Innovation Minister, was not consulted or informed by Mr Johnson before Professor Nutt’s dismissal, despite his office being responsible for co-ordinating scientific advice across Whitehall. He was unavailable for comment yesterday, but said on his Twitter account that he would be “asking why he was not informed, getting facts, and finding a solution”.

Professor Nutt said that the council was no longer tenable as a functioning advisory group. “I can’t believe any self-respecting scientist would serve on it,” he declared. Writing in The Times today, he calls for the creation of a truly independent advisory council on drugs modelled on the way that interest rates are set by an expert committee.

Professor Nutt was sacked after criticisms he had made of the Government’s drugs policy were published in a paper by the Centre for Crime and Justice at King’s College London. The comments were made in a lecture he delivered in July, in which he said that Ecstasy and LSD were less harmful than alcohol and cigarettes. He also criticised the decision to upgrade cannabis to class B.

Mr Johnson insisted that he was right to force Professor Nutt to stand down months after he took over as council chairman. “You cannot have a chief adviser at the same time stepping into the public field and campaigning against government decisions,” he said.

A Home Office spokeswoman said: “We can confirm that Dr Les King has resigned. We are not going to give a running commentary on the speculation around further resignations.”

Dr King said that the Government’s attitude to the council had changed in recent years and that Home Secretaries now had a “predefined political agenda” when they asked for its expert advice.

“It’s being asked to rubber-stamp a predetermined position,” he said. “He \ may be an adviser, but he’s still got the right to say what he likes. That was being denied.”

Leading scientists said that the affair raised issues for scientific advice across government. Colin Blakemore, Professor of Neuroscience at Oxford University and former chief executive of the Medical Research Council, said: “It is the responsibility of ministers, not advisers, to make policy, and the drugs issue is of course particularly sensitive, but there are clearly implications . . . for all areas of scientific advice to government. I’ve served on a lot of advisory committees, and I’ve never seen anything like this. I’m sure that every independent expert who sits on an advisory committee would now like an assurance that the Government remains committed to proper consideration of the recommendations it receives.

“Also, I think it is important that the Government should permit experts to engage publicly in discussion of the basis for their opinions, even when the Government chooses not to accept them.”

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