If I were on a dark stretch of road and saw a cop getting the tar kicked out of him, I would stop and help that cop with whatever force needed. I support the police, I do not take joy in any officer being injured.
This was a stupid accident. It was careless and negligent, and no matter how much anyone tries to attach adrenaline, non existent scenarios, additional victims, angry mobs, and all the other fantastic excuses I've read here, a man took a gun from a trunk and shot himself with it.
There are simple rules to handling firearms, not difficult at all. Again, if I saw someone do something this stupid at a range or gun club, he'd be banned. Regardless of profession.