Calls for a criminal investigation into a minister’s alleged leak from a top secret committee have intensified after police signalled the power to trigger a probe lay with government.
Gavin Williamson was sacked as defence secretary on Wednesday after Theresa May concluded he was the source of a leak from the National Security Council on Chinese firm Huawei’s role in building Britain’s 5G network.
May’s de facto deputy PM, David Lidington, on Thursday attempted to face down a chorus of demands from opposition MPs for a police probe after Williamson protested his innocence, adding ministers would “cooperate fully” with police.
Now Cressida Dick, Commissioner of the Met Police, has waded into the row, underlining a criminal investigation into an alleged breach of the Official Secrets Act can only be triggered when information is shared with them by government.
She said: “The gateway process has been in place for about six years and a formal decision would be taken by the deputy commissioner but that is hypothetical because we have not had any referral from the Cabinet Office.
“We will look at any complaint we may get and if there is relevant evidence we will always look at it.”
Lidington told the Commons on Thursday the government would “cooperate fully” if police launch an investigation, but that Sir Mark Sedwill, the top civil servant who led the internal probe, did not “consider it necessary” to push for a criminal probe.
The PM’s official spokesman, meanwhile, hinting May had weighed up the matter, stressing it was “not about what was leaked, it was about where it was leaked from”.
May said on Wednesday she regarded the matter as “closed” but Labour, SNP and the Lib Dems are demanding police look into it.
Labour deputy leader Tom Watson, said in the Commons that May cannot be “the complete arbiter” of Williamson’s conduct as the former minister had “protested his innocence”.
He went on: “Therefore this matter cannot be, as the Prime Minister says, closed.
“The essential point here is the Prime Minister has sacked the Secretary of State for Defence because she believes there is compelling evidence that he has committed a crime. But despite that, she does not believe he should face a criminal investigation - where is the justice in that?”
Former Attorney General Dominic Grieve said a “progressive breakdown” in collective Cabinet responsibility was to blame.
“Unfortunately what appears to have happened is it has a corrosive quality which starts in the willingness to contradict colleagues over policy issues within the Cabinet and then creeps incrementally into a willingness to brief externally on discussions on an increasingly secret nature,” he said.
Lidington agreed there was a “corrosive effect of unauthorised disclosures” and added: “I do think above all when it comes to National Security Council discussions, and I think this applies to Cabinet too, that there is great merit in the very old-fashioned precept that members should speak with complete candour within the room and shut up when they get outside.”
The SNP’s defence spokesman Stuart McDonald, meanwhile, said it was “not in the Prime Minister’s gift” to say this “most disgraceful episode” is closed.
He added: “The fact we are here today shows that it is far from closed.”
McDonald asked: “What was Mr Williamson avoiding answering?”, and asked what further action would be taken beyond his sacking.
Responding, Lidington said he would not comment beyond what the Prime Minister wrote in her letter to the former defence secretary.
He added: “Whether a criminal offence has been committed is a matter for independent prosecution authorities and ultimately for the courts.”
Other MPs attempted to defend Williamson.
Conservative Gainsborough MP Sir Edward Leigh said “in this country we believe in natural justice”, and when someone is accused of a crime they are “given a chance in an impartial forum to prove your innocence”.
He asked: “As a matter of natural justice, how is the former defence secretary now going to be given the opportunity to prove his innocence?”
Lidington said Williamson had “not been accused of any criminal offence” but had “lost the confidence of the Prime Minister”, who by sacking him “acted within the ministerial code”.