Calls for Official Secrets Act investigation after Gavin Williamson is sacked as defence secretary

MPs last night wrote to the head of the Metropolitan Police demanding a criminal investigation into Gavin Williamson’s conduct.

They demanded to know whether the sacked defence secretary’s actions breached the Official Secrets Act.

Government workers and others can be charged under the act if they are found to have made an unauthorised disclosure of information relating to security or intelligence.

The offence carries a maximum two-year jail term.

In her letter sacking Mr Williamson, Theresa May said she considered ‘the matter closed’ – suggesting she did not want a police investigation.

But last night there were calls for Cressida Dick, the Met Police commissioner, to launch a formal inquiry.

A letter signed by Lib Dem MPs Jo Swinson, Sir Vince Cable and Sir Ed Davey said a probe was needed ‘to ascertain whether the actions of Mr Williamson constitute a breach of the Official Secrets Act, given that the leak originated from the National Security Council and related to highly-sensitive information’.

Labour’s deputy leader Tom Watson and defence spokesman Nia Griffiths also demanded police action. Mr Williamson was at last week’s National Security Council meeting but strenuously denies being behind the leak, which provoked fury in Whitehall.

NSC meetings, chaired weekly by the Prime Minister, are supposed to be held in strict confidence. It is a forum where secret intelligence can be shared by GCHQ, MI6 and MI5 with senior ministers, all of whom have signed the Official Secrets Act. Foreign intelligence is also often discussed, involving key allies.

Labour’s deputy leader Tom Watson (pictured earlier this week) and defence spokesman Nia Griffiths also demanded police action

Mr Watson took to Twitter to demand police action be taken should Mr Williamson have leaked from the National Security Council

Scotland Yard said in a statement: ‘We’re aware of the media reports in relation to the leak and that is a matter for the National Security Council and the Cabinet Office to look at.

‘At this time, we’re not carrying out an investigation.’

It is not necessary to have signed the Official Secrets Act in order to be bound by it and Government employees are usually informed they are subject to it in their contracts.

Many are still asked to sign the act as a way of reinforcing its content.

Prosecutions under the act are very rare. In 2002, former MI5 agent David Shayler was handed a six-month jail term for selling intelligence secrets to the Mail on Sunday.

He claimed MI5 tapped the then Labour MP Peter Mandelson’s telephone, had a file on foreign secretary Jack Straw’s involvement in Left-wing politics and that MI6 tried to bomb Colonel Muammar Gaddafi.

In her letter sacking Mr Williamson (pictured), Theresa May said she considered ‘the matter closed’ – suggesting she did not want a police investigation 

Sir Vince Cable (pictured), who leads the Lib Dems, said: ‘This story cannot begin and end with dismissal from office’

In 1984, Ministry of Defence civil servant Clive Ponting passed details to Labour MP Tam Dalyell about the sinking of the Belgrano during the Falklands War. He was charged under the Official Secrets Act but acquitted by a jury and he subsequently resigned from the Civil Service.

Earlier that year Sarah Tisdall, a clerk at the Foreign Office was prosecuted and jailed for leaking information to The Guardian about when US cruise missiles were due to arrive on British soil.

Mr Watson said last night: ‘It’s the most brutal sacking letter of any minister I’ve seen in my lifetime. The magnitude of the allegation against him is very serious.’ He said because Mr Williamson denied the allegations, the best way for him to have his voice heard would be through a criminal inquiry.

Sir Vince Cable, who leads the Lib Dems, said: ‘This story cannot begin and end with dismissal from office.’