I can see 2 or even 3 rds. to the head but it sounds like this guy emptied the magazine.
What happens when you notice Bad Guy #2 & #3 and you're standing there with your slide locked back?
Not really, he had a few rounds in hand since he was using a Glock 19 and at least two of his immediate back-ups were armed with Sigs. That said, I still have my reservations about how this particular incident went down. The outcome was based on poor intelligence gathering, compounded by lousy surveillance and comms procedures. Set those factors against the prevailing political pressure to "DO SOMETHING" and it's not hard to see why there was a cock-up. The SF back-up teams that were supporting the police on the day should have been given the task (and the choice) of making a soft or a hard arrest.
It's more a question of mindset really. The bobby's job is to apprehend the bad guys and bring them before the courts. The soldier's task (as your own Stormin Norman once aptly put it) is to kill the enemy and break their stuff. When those to psycholgies clash, confusion will reign.
And incidents like these WILL happen again, so long as we continue the dangerous charade of treating a lethal terrorist threat as a purely criminal activity.