HALIFAX - No discipline will be imposed on an RCMP officer who fatally shot a Nova Scotia man in his own home because the force neglected to start a review of the constable's actions within its legally required time frame.

In January, the RCMP launched a disciplinary review of Const. Jeremy Frenette's actions in 2008 shooting of John Simon, weeks after receiving a report by the Halifax police into the incident.

But the review ended shortly after it began once the Mounties realized it did not start the process within a year as required by law, RCMP spokeswoman Brigdit Leger said Thursday.

"It was a gap in our process," said Leger.

"A discipline review was commenced but based on the time that had passed, our ability to continue was questionable ... We regret this."

The revelation drew an incredulous reaction from the Wagmatcook First Nation, where the 44-year-old Simon was killed.

"This is unbelievable," said Brian Arbuthnot, director of operations for the Wagmatcook First Nation's band council.

"It goes to the heart of the mismanagement of the RCMP from top to bottom."

Arbuthnot said the community will be stunned to learn that an administrative error resulted in the review being dropped.

"How can you miss doing disciplinary action in a man's death?" he said. "Words go beyond how I feel about this right now. It's negligence in the highest order."

Archie Kaiser, an expert on criminal law at Dalhousie University, said the RCMP are not providing the public with an adequate explanation.

"Unfortunately, I think the decision not to proceed with disciplinary proceedings will further undermine public confidence in the way in which the RCMP handled this investigation," he said.

Frenette shot Simon dead on Dec. 2, 2008, after the officer climbed through Simon's window and confronted the allegedly drunk and suicidal man.

A report by the Halifax police into the incident concluded Frenette didn't violate any laws and shot Simon in self-defence. The report quoted Frenette saying, "I felt he was gonna shoot me."

But that report also said Frenette was "in contravention of established RCMP policy," and that his supervisor instructed him to stay out of Simon's house.

After arriving at the scene, Frenette had moved closer to the home, up onto a deck and had looked inside the door and windows, according to the report.

Frenette asked twice for permission to enter the home but it was not granted, though he "decided to act alone on this opportunity to catch John Simon unaware," the report said.

The portion of the report that explains why Frenette felt he had to enter the house is blacked out - something that Kaiser said raises more questions about the shooting.

"This underlines the importance of having a full public inquiry into this incident and the issues it exposes," he said.

Patsy MacKay, Simon's widow, said she was informed some time ago that disciplinary actions against Frenette -- who has been moved to another community -- were unlikely.

"It's so obvious to anybody except the RCMP what happened. He acted against direct orders. What kind of policing is that, where you don't obey orders?"

Provincial Justice Minister Ross Landry has ruled out launching a public inquiry, saying it wouldn't "necessarily address" the concerns of the Wagmatcook First Nation.

Leger said the RCMP still plans to follow up on recommendations from the Halifax police report that the force improve its training of officers who are responding to situations where a person is barricaded in their home.