Self defense from a Policeman.

[John Dibble]

Legally speaking, I would say yes.

However, given that you'd be a cop killer (even if you were justified in doing so) you had better damn well hope that the responsibility for investigating the affair is the FBI or some sort of internal affairs from another department. You also better damn well hope that there's overwhelming evidence in your favor. It wouldn't hurt to have a damn good lawyer as well.

[John Dibble]

If such a scenario were to occur carry a  less than lethal weapon of some kind.

So, if such a thing happens to you go back in time and get a less than lethal weapon? *scratches head*