The opposition parties are forcing an emergency meeting of the national defence committee to investigate the government's conduct in the Mark Norman trial.

A charge of breach of trust against Vice-Admiral Norman was stayed last week, a year after he was formally charged with leaking sensitive information about a lucrative shipbuilding contract. He had denied any wrongdoing.

A letter, signed by four Conservative and NDP MPs, was sent Sunday to the clerk of the committee.

The letter alleges that in 2018 the prime minister influenced the case by anticipating that the RCMP's investigation into the matter would result in a prosecution, signalling he had access to inside information.

And secondly, it claims that the government tried to interfere in the shipbuilding contract, then smeared Norman's reputation when information about that attempt came to light.

"This has had a deleterious effect on the morale of the Canadian Armed Forces," it states.

The MPs called for the committee to be reconvened within five days. Four committee members can force a meeting, but the study will not be undertaken unless supported by the majority of MPs on the committee.

At the time the charge was laid against Norman, the Crown alleged he had not only leaked the results of that cabinet meeting to a now-former CBC journalist, but had also provided secret information on 11 other occasions to an executive at the Davie Shipyard which was involved in the lease contract.

Defence lawyer Marie Henein said the Liberal government blocked her from accessing a number of documents needed to defend Norman.

The Mounties released a statement Friday afternoon defending their handling of the entire matter and stating they respect the decision of the Public Prosecution Service to stay the charge.

High-profile witnesses

The Conservatives responded to news of the dropped charge by saying government officials had inappropriately interfered in the case, including delaying the release of documents and coaching witnesses.

The charge was dropped after the defence spoke to former Conservative cabinet ministers about what they knew. The prosecution concluded there was not a reasonable chance of conviction, given the new information.

The letter also asks for testimony from the following witnesses:

Vice-Admiral Mark Norman.

Prime Minister Justin Trudeau.

Minister of National Defence Harjit Sajjan.

Minister of Justice David Lametti.

Minister of Public Safety Ralph Goodale.

Minister of Public Services and Procurement Carla Qualtrough.

Former president of the Treasury Board Scott Brison.

Former minister of Public Services and Procurement Judy Foote.

Chief of Defence Staff Jonathan Vance.

Former clerk of the Privy Council Michael Wernick.

Prime Minister's Chief of Staff Katie Telford.

Former prime minister's principal secretary Gerald Butts.

Orleans MP Andrew Leslie.

Director of Policy for the Minister of Democratic lnstitutions James Cudmore.

The MPs requested that the witnesses appear by May 24 for no less than one hour, and that the meeting be televised.

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