STONY PLAIN, Alta. - A final inquiry begins Monday into how four Alberta Mounties were murdered six years ago, but the mother of one of the victims is more concerned about what has changed to make police safer.

"That's our main area now because we can talk forever -- all of us -- about what happened, but that won't bring my baby back," said Colleen Myrol in an interview from Red Deer, Alta.

"There's going to be a part (at the inquiry) where we can see what was in place for the RCMP prior to March 3rd, and see what they've put in place now. That to me is critical. Otherwise there are no lessons learned.

"If there's any way we can save somebody else's family from going through this, personally, I think that's the purpose of this inquiry."

Her son Brock Myrol was one of the officers ambushed and killed by James Roszko in a Quonset hut on his farm near Mayerthorpe, Alta., on March 3, 2005.

The murders shocked and saddened the nation and to this day produce ripples of heartbreak. They have divided families and disrupted lives.

On Monday, in provincial court in Stony Plain west of Edmonton, Judge Daniel Pahl will begin to hear evidence from witnesses in a mandated fatality inquiry. Such hearings don't assign blame but examine the circumstances of deaths and recommend ways to avoid similar ones.

Myrol, along with fellow constables Anthony Gordon, Peter Schiemann and Leo Johnston were all gunned down by Roszko, a known police-hater and loner with a history of assaults and run-ins with the law dating back to his teens. The 46-year-old shot himself to death in the hut shortly after he ambushed the officers.

It was one of the worst mass murders of Mounties in the history of the RCMP and left behind maddening questions. It has never been revealed how Roszko, who fled his property when authorities came to repossess his truck, managed to sneak back in the pre-dawn darkness while Mounties were guarding the hut.

All died from multiple gun shot wounds from his semi-automatic .308 Heckler and Koch assault rifle.

The public has since learned how Roszko got back to his sprawling property unseen. A two-year undercover police investigation led to the arrest and 2009 manslaughter convictions of Shawn Hennessey and Dennis Cheeseman, who gave him a rifle and a ride to the farm that fateful night.

There have been other reports and investigations that have led to criticism of the justice system and questions about whether the RCMP did enough to keep the officers safe.

Critics say more should have been done to lock up Roszko for his previous offences, which included a conviction for a sex assault on a boy.

In 2005, senior Crown prosecutor Gordon Wong examined Roszko's case file at the request of the provincial government. He found that while Roszko faced almost 40 charges dating back to when he was 17, there were few convictions due mainly to the fact that witnesses would fail to show up at trial.

The list of wrongdoings -- alleged and proven -- was long: theft, fraud, mischief, assault, break and enter, harassment, obstructing justice, pointing a gun and threatening murder.

Wong said prosecutors had begun to build a case to try to convince a judge to designate Roszko a dangerous offender, which would have locked him up indefinitely. But, Wong said, there just wasn't enough evidence to make it stick. The dangerous offender tag is reserved for the worst of the worst.

"The Crown vigorously prosecuted Roszko to the fullest extent possible," said Wong in his report. "The trials or preliminary inquiries that were conducted were all hard-fought contests."

In 2006, an internal RCMP investigation determined that officers need better body armour to protect them from long-barrel weapons. It also said more needed to be done to keep track and spread the word amongst officers on violent offenders such as Roszko.

Investigators said portable radio communications devices needed to be improved for rural officers. And they suggested more target practice in an effort to help officers react instinctively in crisis situations.

At Hennessey and Cheeseman's hearing, court was told that only Johnston managed to get a shot off at Roszko, though the bullet harmlessly glanced off the butt of a gun tucked into his waistband.

Sgt. Tim Taniguchi, spokesman for the RCMP's Alberta division, said the force welcomes the fatality inquiry.

"We're committed to our members and to communities, and we look forward to the recommendations that will be made."

The case has spawned a book, a made-for-TV movie and millions of words in the mainstream media. Aerial shots of the Quonset hut -- a long, deep, gun-metal grey half-cylinder surrounded by mud and streaks of dirty snow -- has become a symbol for the tragedy.

The pain of the deaths continues to visit misery on families and friends. In 2008, Johnston's remains were moved from his hometown of Lac La Biche, Alta., to the RCMP cemetery in Regina at the behest of his widow and against the wishes of his parents. It got ugly. At one point, those who opposed the move set up a picket line at the cemetery to prevent workers from exhuming the remains.

Two RCMP officers who were colleagues of the dead constables have said they broke down emotionally after being ordered in subsequent days to investigate the crime and work with family members of the victims. They have sued the RCMP for negligence.

Rev. Don Schiemann, father of Peter, said he dreads sitting through two more weeks of detailed testimony on how his son died.

"I'm not looking forward to it. I'm going to have to relive certain things," he said in an interview from Stony Plain.

"It's been six years. We've heard (the story) over and over again."

He declined comment on what he expects the hearing to deliver.

"Until we've actually heard what needs to be said, it's hard to determine that."

Colleen Myrol has a list of witnesses and evidence to be presented, and she and her husband will choose when to attend.

"I've gone through some of the material and it's quite difficult," she said.

"I don't need to go again and hear again all the gory details. I know what they are."