Zehaf-Bibeau died in a hail of gunfire outside the Parliamentary library after first shooting Cpl. Nathan Cirillo at the National War Memorial, then wounding a security guard at the entrance to the Centre Block on Parliament Hill.
Day's analysis of the tape suggests that Zehaf-Bibeau probably exhausted the maximum number of bullets that could be loaded into his Winchester .30-30 calibre rifle in the moments before he died.
- One that wounded Samearn Son, the guard at the front entrance.
- At least two more at the rotunda near the entrance.
- Another two in the Hall of Honour as he ran towards the library
If correct, this means Zehaf-Bibeau would have needed to reload, with officers closing in on him, before firing what Day says is one final shot.
That can be heard on CBC News videotape, just before he was cut down by semi-automatic pistol fire from Sergeant-at-Arms Kevin Vickers and other officers.
'Incredibly difficult shot'
Silos and stovepipes
At one point, a House of Commons guard can be heard saying that he doesn't know if the gunfire is inside or outside the building. Meanwhile, the gunman was firing his weapon just metres from the prime minister, who was in a caucus meeting with his MPs next to the Hall of Honour.
The Senate and House security guards are under separate commands. The Ottawa Police, the RCMP and its plain-clothes protective detail for the prime minister were also involved.
Day said this fragmentation of agencies is reflected in Canada's security infrastructure as a whole.
"This is symptomatic of some of the larger issues that we have in Canada with respect to moving our architecture and our lens from the 20th century and the Cold War paradigm into the 21st century and an adversary that is globally networked."
As it stands, Day added, "it's siloed and stovepiped. So, inside Public Safety, inside DND,(Department of National Defence) and inside Foreign Affairs,you've got silos of information that don't necessarily translate down to the folks on the shop floor."
"It's not necessarily the individual officers that's the problem, as it is a systemic issue about how we bring together those different security forces, actors, so that we've got a coherent approach."