Let's all back up a moment here. The copper got off 6 shots but apparently took 2 and went down. If the cop had a wheelgun, well, he'd have an empty revolver and still be dead. Shot placement, caliber and luck all count as much as reliability. With that being said:
I was never a fan of the 92FS design, that un-housed barrel scares the bejezus out of me. You never know what can creep in there and cause just enough friction on the slide, slow down the momentum and jam the gun. I'm not saying this is what happened or that it happens often or even at all, it's just something that always stuck out to me.
Things like that catch my attention. The fact that I carry my USP cocked and locked, I noticed that lint and other debris like to settle into the hammer channel. I clean that with a Q-tip once per day because it seems to me that debris is just not a good idea. But what do I know?
Revolvers can fail. Very rarely, but they can. I don't think the failure killed this cop necessarily, the 6 shots that didn't put the BG down had more to do with it I think.
To those advocating that this is a good reason to carry a revolver instead of an automatic, I disagree. That's a personal choice. There are only so many variables you can isolate. There is always a chance that the round in your revolver is defective. Many rounds leave the factories every year with some type of defect, many of them can not be discerned with the naked eye...you have to shoot them to find out.
Find the biggest caliber you can shoot effectively.
Train. Train. Train.
Cary a firearm of good quality that you know works.
Train. Train. Train.
Perform routine maintenance on your firearm (inspection and cleaning).
Train. Train. Train.
Regardless, sad thing it is.