Curios...I was watching City By the Sea last night and wondered about a comment that Robert Deniro's character said; "You could plead self defense...maybe only get six years." Now I know anything can happen in a courtroom but this sounded odd to me. Is it possible that self defense could still get you time? The State was New York.
I'm not familiar with NY law or with that movie, but unless NY is kinda wacky compared to everyone else, I see three possibilities:
(1) the De Niro character was not any kind of legal expert and was just offering advice "outta his ass," for lack of a better word--i.e. he was just saying something the average Joe might think is true, even though it's actually not; or
(2) the screenwriter(s) didn't know what they were talking about; or
(3) the circumstances were such that the person was acting in self defense
but they overreacted, using force out of proportion to the injury they feared. In that case, what they did WAS a crime, because to be legal, self defense has to be reasonable (i.e. pretty much in proportion) under the circumstances. You can kill someone who's trying to rape you, but you can't kill someone who's trying to slap you; with the slapper, you can maybe grab their hands or punch them once or something, but you can't do something a whole lot worse than what you think they'll do to you.
But in that case, where a person did overreact
but was doing so in self defense, the self defense argument goes to motive or state of mind, and thus mitigates the crime and the sentence. For example, if you stab someone in self defense when you had no reason to think they would do anything more than punch you once or twice, and they die from that one stab wound, then, even though killing them is a crime, in that situation it does not constitute first-degree murder. It might not even be murder at all, but just some kind of manslaughter (I can't say for sure because every state's law varies and I don't know what the circumstances of the killing were).
To clarify what I mean, note that all crimes have what's called "elements." Here's a simplistic example: let's say that in state X, the elements of first degree murder are (a) purposely killing someone with (b) malice aforethought (i.e. you planned the killing in advance in cold blood). Element (b) is the one that goes to the perpetrator's motive and/or state of mind. So if you were in state X and you purposely killed someone, but
not with malice aforethought, just in the heat of the moment, what you did is not first-degree murder because you didn't have the requisite "malice aforethought" state of mind. With the state of mind you DID have, maybe under the laws of state X, what you did would add up to
second-degree murder (a.k.a. "murder 2"). (All of these distinctions--the exact elements that add up to murder 1, 2, 3, or manslaughter 1, 2, etc.--vary from one state to another). So, maybe in that movie, what the De Niro character was saying basically meant, "if the jury buys the self defense argument, then they can't find you guilty of murder 1 or 2 because you didn't have the necessary motive/state of mind to be guilty of murder 1 or 2. With the 'self defense' state of mind, the most they could find you guilty of is manslaughter 1, and the punishment for that is only 6 years."