raydan raydan:
One of the arguments here is that all gun owners are excellent shots that would have no problems taking down the shooter. The problem with that argument is that the shooter is also a gun owner.

Very few criminals practice with a firearm.
Although when they do it can be very deadly.
http://en.wikipedia.org/wiki/2011_Norway_attacks~
For all the comments about how it's easy when no one is shooting back, please remember the only people shooting were the police. The killer only fired to kill the guy he set out to murder. When the police started shooting he was not returning any fire.
It might be more correct to say, when you are excited it can be hard to do fine motor skills with accuracy. Which is why most military weapons training is repeated so many times, so that when it comes to a real fight your body will know what it needs to do without your mind trying to actively control your movements. I will suggest the police don't dedicate as much time to learning and practicing their pistols as they do to other police skills.
I doubt I will ever forget how to work a C6 (FN MAG).
~
Bystanders were hit with bullets and bullet fragments, not just with fragments.
What the police did was a close to a mag dump. Getting as many shots off as they did as fast as they did is how you miss your target from less than 3m. You can watch a rather poor video of the shooting but it doesn't add much as it's damn short and kinda blurry.
Again I will suggest the solution is a heavier longer weapon that uses two hands well spaced apart. Semi automatic fire with a pistol round is very controlable in a PDW or SMG. But they are larger, take up more space, look scary (to people that let their feelings do the thinking), cost more, may get in the way more often when trying to do other types of police work.
It is possible to be a very good pistol shooter, but it take time and dedication. For the number of times the police kill or hurt bystandards it might be better to have them out on the streets rather than at a range working towards being safer.