The Quebec government has ordered an independent investigation into information leaked to the media in the high-profile case of a retired officer alleged to have been collaborating with the Mafia.

Public Security Minister Robert Dutil said Wednesday that he wants provincial police to investigate circumstances of the Ian Davidson case and find out how the media learned about it.

The Crown prosecutor's office called for the probe announced Wednesday. It said an investigation into Davidson's activities had been underway when someone informed journalists, and said it wanted to know how that happened.

Such Crown requests are rare but, in this case, there are hints charges might be forthcoming.

"We allege ... that there were leaks of information that were privileged, sensitive and highly confidential that came out in the media and we need to know how they came out," said Jean-Pascal Boucher, a spokesman for the Crown.

"We allege that a criminal act might have been committed in divulging this information."

Alleged offences occurred after detective's retirement

A recent example of such a Crown-triggered investigation was in March 2011, when the body ordered a probe into Boston Bruins defenceman Zdeno Chara for a bone-jarring hit on Montreal Canadiens Max Pacioretty.

'The release of confidential information in the media undermines police investigations.'—Montreal police chief Marc Parent

The hockey probe lasted months and resulted in no charges against Chara.

This latest case involves allegations that a Montreal police officer sold the names of police informants to the Italian Mafia.

Davidson, 58, committed suicide on Jan. 18, the day he was publicly outed as a mole in newspaper reports. Montreal police had not identified him as a suspect but did confirm that a 33-year veteran of the force was under investigation.

The alleged offences occurred after Davidson's retirement from the force in January 2011. He had been under police watch since last spring and was actually arrested at the airport in October.

Even following Davidson's death, the media leaks haven't ceased: multiple stories have appeared about the so-called Davidson affair since he killed himself.

The endless stories have shocked Montreal's police chief, who welcomed the provincial police investigation. He said the leaks were harming the investigation into criminal ties.

"I was concerned, and angry, to read, day after day, confidential information in the media," Marc Parent told a hastily called news conference on Wednesday.

"The release of confidential information in the media undermines police investigations."

Journalists' association concerned about scope of investigation

News of an investigation into the source of the information had some media questioning whether authorities were going to use the mandate to crack down on journalism.

Brian Myles, a newspaper reporter and president the Federation of Professional Journalists of Quebec (FPJQ), said journalists were doing their job by reporting on the misuse of the informants' list and had a right to report on the stories.

"We're concerned with the scope of the mandate given by Mr. Dutil," said Myles. "We want some assurances that it's not going to be a fishing expedition into the sources of reporters."

Myles said protection of sources is of the utmost importance and he wants to know that the relationship between reporters and police sources is not under the microscope.

Parent said an internal investigation into the alleged Davidson leaks is on going with the assistance of the RCMP and the provincial police.

Police databases have also been secured in the wake of the leak allegations. Parent said senior police brass – in particular the specialized units – were reminded of their oath of discretion.

It's unclear whether the leaks actually came from inside the police force. Parent said some of the information that had appeared in the media was untrue, without offering specifics.

On Tuesday, the opposition Parti Québécois had demanded a public inquiry into the Davidson affair.