The RCMP say they conducted a "thorough" investigation of Vice-Admiral Mark Norman, whose criminal case ended dramatically this week when the Crown stayed a single charge of breach of trust.

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.

The comprehensiveness of the investigation into the military's former second-in-command was called into question when it was revealed that the case was dropped because of new information unearthed by Norman's defence team.

"Throughout the course of this criminal investigation, investigators from the RCMP National Division Sensitive and International Investigations section have conducted a thorough, independent and highly professional investigation," said the statement.

The Mounties started their probe after the results of a Nov. 19, 2015 cabinet meeting on the future of a plan to lease a supply ship for the navy were leaked into the media. The Liberal government, newly elected at the time, was forced to retreat on its plan to put the $668 million project on hold.

By 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.

The new evidence presented to the Crown — by the defence — included interviews with Conservative cabinet ministers and staffers who had not been interviewed as part of the original investigation.

"The RCMP didn't have it, and didn't look for it. I don't think they were suppressing anything," said Marie Henein, Norman's lead defence attorney, when asked Wednesday whether the evidence which cleared her client was deliberately ignored.

Did the Mounties drop the ball?

Former Conservative ministers Jason Kenney, Erin O'Toole and Peter MacKay acknowledged this week that they spoke with Henein and it's believed the information they provided helped to get the case dropped.

Speaking to CBC News Network's Power & Politics on Friday, MacKay said he was unsure if any information he gave to Norman's defence team contributed to the charge against Norman being stayed — but if it did, or if the information provided by Kenney or O'Toole did, the RCMP should have been able to find it on their own.

"It seems in retrospect that there were a number of people that ... I would have expected (the RCMP) to have interviewed in more detail about the case, given that the single count indictment of breach of trust covers a period of time in which the Conservative government, ministers like myself, minister Kenney and others, could have and would have had relevant information that was not requested," MacKay told host Vassy Kapelos.

"And so that is a question of operations and investigative techniques that the RCMP will have to answer for."

The RCMP investigation also resulted in a breach of trust charge being laid against a federal procurement official, Matthew Matchett. He is accused of leaking cabinet documents related to the same meeting.

That case is still active and will go before a judge for a preliminary hearing in the fall. For that reason, the RCMP won't say anything more about their handling of the case.

"As certain elements of this investigation are still before the courts, we have to let the legal process continue its course and will therefore not be commenting any further at this time," said the statement.