An officer in a cruiser could have blocked Zehaf Bibeau's path to the Centre Block but for a woman pushing a stroller who tried to jump into the car for safety.
A radio alert that a gunman was on Parliament Hill was so garbled that no one understood it.
And the majority of security forces are stationed inside the Parliament Buildings, not outside.
None of the officers stationed on the grounds stopped the gunman before he got through the doors, the result, the RCMP say, of systemic security issues, not human error.
"There is nobody from our perspective that is to blame for this," said RCMP assistant commissioner Gilles Michaud. He added no one has been disciplined for their actions on Oct. 22.
Yet the events from last October remain a "grim reminder that Canada is ill-prepared" to stop terrorist attacks, with the RCMP suffering a lack of "planning, training and resources" to protect the Parliament buildings, a long-awaited Ontario Provincial Police report says.
The report, one among several released Wednesday, says the RCMP's ability to protect Parliament Hill has been stretched by resource issues stemming from budget cuts imposed in 2012 by the Conservative government.
"Fortunately," the report says, "the attacker was unorganized."
Had Michael Zehaf Bibeau been better prepared, "the end results could have been much worse with the likelihood of many more casualties" and "devastating results."
The details in the OPP report provide a graphic account of Zehaf Bibeau's attacks, the death of Cpl. Nathan Cirillo and the dramatic takedown inside the Centre Block that ended with the sergeant-at-arms in a sitting position emptying his gun's magazine as Zehaf Bibeau crumpled to the floor.
Zehaf Bibeau fired one shot into Cirillo's back from about three metres away as Cirillo stood guard at the National War Memorial, just off Parliament Hill. Cirillo fell on his hands and knees and crawled away. Zehaf Bibeau then fired another shot into Cirillo's back.
Cirillo got to the east side of the Tomb of the Unknown Soldier where he lay prone on his stomach. "Zehaf Bibeau moved towards the fallen soldier and fired a third and final shot into the back of Cpl. Cirillo," the report says.
Zehaf Bibeau turned towards the Langevin Block, which houses the Prime Minister's Office, and yelled "Iraq." He then ran towards Parliament Hill as bystanders struggled unsuccessfully to save Cirillo's life.
A tourist pushing a stroller saw Zehaf Bibeau run onto the Hill and warned a Mountie sitting in a cruiser near the East Block. The woman tried to get into the back seat of the cruiser and delayed the officer long enough that Zehaf Bibeau drove by in a commandeered vehicle.
Michaud said that Zehaf Bibeau wouldn't have made it to the Centre Block without that car.
Michaud said the officer tried to radio others about the gunman's presence, but her message couldn't be understood.
Inside the Centre Block, Zehaf Bibeau was shot 31 times, with the first bullets hitting him seven seconds after he burst through the front door.
Two of those shots would have been fatal: One through the back of his neck perforated his brain, the other went through his back and pierced his heart. The OPP report says there is evidence Zehaf Bibeau's heart was still beating after both shots.
The report includes 66 recommendations for increasing security around Parliament Hill, including a references to long guns for the RCMP, and identifies ongoing security issues such as unfettered public access to the lawn of Parliament Hill and ongoing construction to the Parliament buildings that requires numerous construction workers and commercial vehicles to move around Parliament Hill daily.
"Parliament Hill is a symbol of Canadian democracy," the report says.
"If Canada is to remain vigilant and proactive in dealing with threats directed to this country, there has to be a willingness to implement changes to protect this area."
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