Alan Johnson was accused today of making drugs policy according to “political expediency” and of humiliating David Nutt by sacking him over a personality clash. The accusations came from the latest senior scientist to resign from the Government’s expert drugs panel.

Simon Campbell, a former president of the Royal Society of Chemistry, said he had quit because the Home Secretary had marginalised the Advisory Council on the Misuse of Drugs (ACMD) and made a scapegoat of Professor Nutt.

Two other members of the council, John Marsden, a research psychologist at the Institute of Psychiatry, and Ian Ragan, a pharmaceutical consultant, also resigned last night after a face-to-face meeting with Mr Johnson. They joined Les King, a chemist, and Marion Walker, a pharmacist, who resigned last weekend.

Dr Campbell, who held senior positions at Pfizer, the pharmaceutical company, said Mr Johnson had failed to address his concerns about the sacking of Professor Nutt for questioning classification decisions on cannabis and Ecstasy, and the Home Office’s attitude towards scientific advice about drugs.

“Going into the meeting I as very uneasy about its dismissal, very uneasy about its manner, and very unhappy about the way the council was being treated,” he told The Times. “The Government took a position on cannabis before the council had considered the issue and reported.

“I told him I didn’t accept the reasons he gave for sacking Professor Nutt, who was made a scapegoat because of a personality clash. The Home Secretary did not respond to that comment.

“I feel there has been a personality clash, and I don’t believe the Home Secretary understood the repercussions. The manner of the dismissal was so abrupt that it was a humiliation.

“It’s about building trust, and this decision eroded a lot of trust. It made it clear that politicians make decisions based not on science but on political expediency. They ask: ‘where are the votes in this?’”

Dr Campbell said it is essential for Mr Johnson now to rebuild the ACMD, and that this would be easier if he stepped down. “This is an essential advisory council, the expertise is tremendously important, and it should be reconstituted and rebuilt,” he said. “I felt that I didn’t really want to start from square one, that it was time for new faces.”

There are now very few scientists left on the council, Dr Campbell said, and it might be difficult to persuade new ones to join: “I think if I were a new person asked to serve, I would ask: ‘why have six eminent scientists gone?’”

Despite the three resignations, the remaining members of the ACMD issued a joint statement with Mr Johnson describing the meeting as “very constructive.”

The statement said: “The Home Secretary emphasised the value he placed on ACMD’s advice, the important contribution the ACMD had made to government drugs policy in the past and how he expected it to continue do so in the future. The ACMD summarised their concerns regarding how their advice is received by the Home Office and over the dismissal of Professor Nutt.

“The discussions were very constructive and it was agreed that the ACMD would continue discussions with the Home Office and Government chief scientific advisors in establishing a way to work collaboratively together into the future with the common purpose of reducing drug-related harms in the UK.”

Mr Johnson said that a statement of principles on the independence of Government science advice, proposed by more than 50 senior scientists, was being considered by the Prime Minister and the Government’s chief scientific adviser, Professor John Beddington.

Lord Drayson, the Science and Innovation Minister, told The Times last week that the Government would accept the principles, though certain details have still to be agreed.

A Home Office spokesman said that it would provide further details “in the near future” of how the department and council would work together and how advice from the council was considered by ministers.

Some members of the ACMD had wanted Mr Johnson to apologise for sacking Professor Nutt, but The Times understands that no such demand was made at yesterday’s meeting. The Home Secretary gave assurances about meeting the council before rejecting its advice in future. Professor Beddington also met the council to discuss their concerns over the continued independence of their scientific advice.

The departures of Dr Campbell and Dr Ragan are particularly damaging as they leave the council without representation from the pharmaceutical industry, which is required by law. Professor Walker’s resignation had already left the council without a pharmacist, another required discipline.

Professor Nutt said of the resignations: “I’m not surprised. The way I have been treated was reprehensible, and I’m pleased to have the support of these other council members.”

Evan Harris, the Liberal Democrat Science spokesman, said: “The latest resignations represent a deepening in the crisis of confidence of scientists in the Government — in particular, in the Home Secretary. That they come after Alan Johnson met the ACMD demonstrates that he just doesn’t get it when it comes to the importance of respecting the academic freedom and integrity of independent, unpaid, science advisers.

“Ministers are entitled to their own opinions, but not to their own facts. “By clumsily and unfairly sacking David Nutt, Alan Johnson has been rewarded with five resignations in protest. That takes a certain kind of ineptitude.”

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