OTTAWA -- RCMP investigators say they're not sure why the Mark Norman case collapsed because they haven't seen the new evidence that led to the stay of a breach-of-trust charge against the naval officer.

The Mounties also suggested that former Conservative ministers -- a possible source of the fresh evidence given to defence counsel -- could have come to the RCMP with the information at any time.

In an interview Tuesday with The Canadian Press, two RCMP officers involved with the Norman probe emphasized the importance of independence in their work, even as opposition MPs continued to accuse the Trudeau government of orchestrating the investigation.

"We follow the evidence and we seek the truth," said Supt. Mike MacLean, criminal operations officer for the RCMP's national division.

Norman, a vice-admiral who served as the military's second-in-command, was charged with breach of trust in 2018 following a two-year criminal investigation into the alleged disclosure of classified government information.

The case revolved around a November 2015 decision by the newly elected Liberal government to reconsider a $700-million contract the Harper Conservatives awarded to Quebec-based Davie Shipbuilding.

Davie was hired to convert a civilian vessel, the MV Asterix, into a temporary resupply ship that would be leased until a permanent replacement was ready.

While the plan to revisit the contract was supposed to remain secret, court documents showed the RCMP suspected Norman of being upset with the decision over concerns the government would cancel the project.

Norman was commander of the navy at the time and, according to the documents, allegedly worked with Davie to pressure the government to keep the project afloat.

In staying the charge last week, prosecutor Barbara Mercier said the Crown believes some of Norman's actions, including his communications, were inappropriate.

However, the ultimate conclusion -- that those actions did not cross the threshold of criminality -- were informed by fresh material she had received from the defence.

It's up to the federal prosecution service to decide whether to share the information with the RCMP, MacLean said.

"Unfortunately, we have not seen that evidence yet," he said. "We'd like to get the totality of the information and do a proper analysis."

As a result, MacLean said, it is premature to comment on whether he now sees the Norman probe differently.

The case's collapse has prompted questions about why the Mounties did not interview ministers in the former Conservative government of Stephen Harper, including Jason Kenney and Peter MacKay, both of whom spoke to the defence.

But the RCMP suggests the former cabinet members could just as easily have approached the police force with details casting Norman's actions in a different light.

"The door is always open," said MacLean.

Staff Sgt. Denis Beaudoin said people contact the RCMP about various files "all the time."

"It's anybody's right to come forward to talk to police," he said during the interview.

The Mounties insist their work on the Norman file was thorough, independent and highly professional. But the case's demise comes as the RCMP faces a lawsuit from Sen. Mike Duffy, stemming from the dismissal of fraud, breach of trust and bribery charges against him.

The force points to successes on other high-profile, sensitive investigations -- from the conviction of former Stephen Harper aide Bruce Carson for influence peddling to the imprisonment of a Royal Canadian Mint worker for stealing $190,000 worth of gold.

The case of a public servant accused of leaking cabinet secrets about the naval contract continues, with a preliminary hearing set for October. Matthew Matchett, a suspended Public Service and Procurement Canada official, has pleaded not guilty to a charge of breach of trust.

Meanwhile, the House of Commons national defence committee is slated to meet Thursday to discuss a request from opposition members to study the government's conduct in the Norman investigation.

Justice Minister David Lametti said Tuesday that each component of the justice system did its job in the Norman case. The prosecution service, in particular, took evidence, evaluated it, decided to lay charges and then elected to stay those charges in light of new information, he said.

"I think that's indicative that the system works."