If you kill someone unintentionally out of negligence...

...is it an accident?

Chicago Police: Woman accidentally killed by officer fire

The officer opened up on a target without even the slightest regard for who might be behind the target. The officer intentionally pulled the trigger. The death might have been unintentional but it was no accident. Now I'll be interested to see what action the Chicago Police Department takes against their officer. I'd bet none.