Kent County Council has been accused of gagging free speech after threatening disciplinary action against a public health specialist who criticised its pension investments in tobacco companies.

Dr Marion Gibbon, who is in charge of stop-smoking schemes for the council, spoke out in a radio interview highlighting the dangers of smoking.

Now the authority, which has responsibility for public health, has told her she faces disciplinary action.

After the BBC interview, she was told by her manager and an HR adviser that she could either accept a warning being placed on her record for 12 months or face a full-scale disciplinary hearing.

The move has been heavily criticised by unions, who say it represents an attack on freedom of speech and bullying.

Unite regional officer Ian Methven said: "What is at stake here is the freedom of speech for a public health specialist to speak out on issues well within her remit, and professional competence and expertise.

"We call on the council to withdraw this threat of disciplinary action immediately and to acknowledge its error in using the new ?protected conversation? legislation as a tool to discipline employees.

"Health professionals should be allowed to conduct their work without these threats to their careers and livelihoods."

He added: "This is not about the health risks of smoking, but a question of free speech and the public interest which Unite will strongly fight to uphold. "

Mr Methven appealed to council leader Paul Carter to intervene to lift the threat of disciplinary action.

In the interview, Dr Gibbon said it was difficult to defend the council's pension investments with tobacco companies when it had responsibility for improving public health.

Kent County Council has defended its action, saying the interview was in breach of its personnel policy that did not permit unauthorised statements to be made to the media.

A spokesman said: "Kent County Council has been dealing with what appeared to be an unauthorised media interview conducted by one of its employees. Any unauthorised statements to the media are a breach of the council’s employment policies.

"This is an internal matter between KCC and a member of staff and in our opinion these issues should not be discussed through the media."

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