Andrew Leslie set to testify for the defence in Mark Norman's breach of trust trial

Retired lieutenant-general Andrew Leslie — who this week announced he's retiring from the federal Liberal caucus this fall — is expected to testify for the defence in Vice-Admiral Mark Norman's breach of trust trial, CBC News has confirmed.

The one-term Ottawa-area MP "self identified" as a potential witness over a year ago — around the time Norman, his former colleague and protégé, was formally charged by the RCMP — sources tell CBC News.

Norman, the former commander of the navy who also separately held the post of vice chief of the defence staff, has been accused of leaking cabinet secrets in relation to a $700 million shipbuilding deal to lease a supply vessel.

Leslie would have no specific knowledge about the allegations that led to the charge against Norman. He would, however, have insight into how the case was treated by the Liberal government, both during the investigation and throughout the pretrial phase.

His testimony has the potential to be politically embarrassing for the government.

Leslie did inform officials in Prime Minister Justin Trudeau's office of his willingness to testify. A senior official, speaking on background, said Friday that no one attempted to pressure him to change his potential testimony. The official also said Leslie's participation in Norman's trial to testify did not play a role in his decision not to run again in October's general election.

 Norman's lawyers have alleged political interference on several different levels, claiming that the Prime Minister's Office and the Privy Council Office have attempted to orchestrate the prosecution of the case. They also have alleged that former Treasury Board president Scott Brison tried to kill the lease deal on behalf of a rival shipyard.

The Liberal government, the public prosecution service and Brison have all denied the accusations, which were made in court and in court filings.

Leslie has not answered CBC's requests for comment. Norman's lawyers also have not responded.

The case is due back in court next week, when the defence is expected to argue for access to thousands of pages of federal government documents related to the investigation and the leasing deal with the Davie Shipyard in Levis, Que.

Closer to the end of this month, Norman's lawyers are expected to present a motion to have the case dismissed, arguing political interference, among other things.

Leslie could become a key witness if the case gets to trial — and not only because of his experience as a member of the Liberal government.

He commanded the Canadian Army for a number of years and has unique knowledge of the inner workings of the Department of National Defence and the many challenges the military has faced in procuring equipment.

Early on in the case, the defence said Norman was caught in a "bureaucratic crossfire." Leslie's testimony about the various players could be key to making that argument.

Dave Perry, a defence analyst at the Canadian Institute for Global Affairs, said that if the case goes to trial, Leslie would fall into the category of 'expert witness'.

"He's got a solid understanding of how someone who is in the position Admiral Norman was in would interact with government, or could interact with government," he said.

"He would probably be able to provide testimony (about) how the head of the army, navy or air force would interact with different political figures, the prime minister, the prime minister's office, the minister, the minister's office, the media. All of those kinds of things. And I think Andrew Leslie would be an expert in al of those aspects."

Norman's lawyers have not yet finalized a witness list because it is unclear whether the case could be thrown out, said sources.

The Crown's preliminary list of potential witnesses was filed with the court last December. It included not only Brison but former defence minister Peter MacKay and former CBC journalist James Cudmore, to whom Norman is accused of leaking the results of a November 19, 2015 cabinet meeting.