Three former federal cabinet ministers have confirmed they spoke to Vice-Admiral Mark Norman's defence team about information that may have been key to the Crown's decision to halt the criminal prosecution of the military's former second-command.

Peter MacKay, who held the justice and defence portfolios, Erin O'Toole, the former veterans affairs minister, and Jason Kenney, the last defence minister in former prime minister Stephen Harper's government, all say they spoke to lawyers representing the career naval officer.

Norman was charged with a single count of breach of trust, kicking off a high-stakes political drama that reached a climax Wednesday when prosecutors stayed the charge.

CBC News reported Wednesday night that the case began to collapse in March — partly under the weight of information suppled by the ex-ministers and by several former Conservative government staffers who were key players in the previous government's decision in 2015 to lease a supply ship for the navy for $668 million.

Norman, the former head of the navy, was accused of leaking cabinet secrets on 12 occasions to the Davie Shipyard — the Levis, Que. operation which won the supply ship contract — and former CBC journalist James Cudmore.

None of the Conservatives were ever formally questioned by the RCMP or the Crown before the breach of trust charge was laid a year ago.

Both MacKay and Kenney said they believe the information they gave the defence factored into the eventual decision to stay the charge.

"Absolutely," MacKay told CBC News in a telephone interview from Minneapolis on Thursday, adding that his discussion with Norman's Toronto-based lawyer Marie Henein "was very involved." He said he made it clear to Henein that Norman was working with the full support of cabinet to deliver the temporary supply ship.

MacKay said he was contacted only once by the RCMP on the "very narrow issue" of an email exchange he had several years ago with Norman.

The National Post reported Thursday that Kenney also had a long conversation with Henein, which has since been confirmed by CBC News.

Document delays frustrated defence: O'Toole

In an Instagram post, Kenney said that as minister of defence he "worked directly with then-commander of the navy, Vice-Admiral Mark Norman, to come up with an accelerated process which ended up with the cabinet deciding to sign a contract with Davie Shipyards to produce an interim joint supply ship."

The meeting with Norman's lawyers, he said, took place last year in Toronto and he "gave them information, which I believe would have helped with his exoneration had this case gone to trial."

O'Toole said he also spoke with the defence team, but does not believe what he said would have been material. He said he questions how critical the information provided to the defence by Conservatives was to the decision to stay the charge against Norman.

"I think it's a simplification to say that the defence questioned a few Conservatives and that led to this going away," he said.

The Crown "didn't question me and they clearly felt they had a case against Admiral Norman before," O'Toole added. "I really think it was the slow and deliberate delays by the Trudeau government on the release of information that Mark Norman needed to defend himself."

Smearing the Mounties?

Neither the Crown nor the defence would say what information led to the case being abandoned. Henein told reporters at a news conference on Wednesday that the information uncovered by her team was directly related to the lease contract four years ago.

The Conservatives faced attacks on social media on Thursday, with some suggesting they should have come forward sooner to help clear Norman's name.

O'Toole fired back, saying former prime minister Stephen Harper publicly offered to waive cabinet secrecy surrounding the agreement — something that was rejected by the Liberal government.

Arif Virani, the Liberal parliamentary secretary for justice, accused O'Toole during question period today of trying to smear the Mounties.

"What I think is important to underscore is there are men and women in uniform, namely the RCMP, that took charge of the very investigation that he's impugning," he said. "And he's impugning the law enforcement officials and the independence of their work."

Henein told reporters that the information the defence presented to the Crown at the end of March was something that would have been in the possession of federal bureaucrats — but was not shared with either the RCMP or the Crown.

New Democrats have called for an inquiry to find out who withheld the information.

Norman said he wants to get back to work and the military's top commander has said he would welcome Norman's return.

"We have missed Vice-Admiral Norman a great deal and I look forward to welcoming him back to work as soon as possible," Gen. Jonathan Vance, chief of the defence staff, said Wednesday.

The two have not met to discuss when that will happen, nor what job Norman would do once reinstated, said a spokesman in the office of the chief of the defence staff.