Well, I do. We had a case in Germany a few years back where the police served some kind of no-knock warrant, the guy (a Hells Angel) thought they were from a rival gang, shouted at them and then shot at them. A Policeman died, the guy dropped his gun immediately after police identified themselves. The Case made the news later because the guy got acquitted of all charges regarding the killing [1] but that's only secondarily relevant here.
For me the main take-away from this should be that there's a difference between shooting back at night against a home invasion and shooting at the police. Just because the police see a situation where someone shoots back in a home invasion-scenario does in no way mean they can expect an intention to shoot at cops. Shooting back at invaders is legal, and the police should not react until they have ruled that out.
[1] I suspect that's a german source, sorry. http://www.spiegel.de/panorama/justiz/0,1518,795678,00.html#