Uh...just how the heck were we supposed to know that? How were we supposed to know that "it was just for laughs?" I mean, he seemed pretty darn serious about needing a ride out of there. And just for the record, it's not Halloween. It's July, folks.
Agree. But, see, that is a nice encapsulation of the problem.
In many jurisdictions, state law doesn't offer one a defense of "how was I supposed to know?" An honest, law-abiding citizen with only the best of intentions who uses deadly force and made an honest, good faith mistake can not only be made to defend himself against an investigation and civil suit -- he can be prosecuted criminally!
Some states / jurisdictions have made a policy choice that in shorthand is essentially "using deadly force is so serious a matter that we want to discourage it in all possible circumstances that don't truly require it, and one way to discourage it is to shift all risk of even a good faith misunderstanding to the person who elects to use deadly force."
The MO statute that jlrhiner posted appears to do that with respect to a private person attempting to make an arrest -- the individual must reasonably believe certain circumstances were true . . . AND the circumstances have to be actually true!
Classic cautionary tale used to illustrate the point: citizen walking along a sidewalk passes across the end of an alleyway and sees down the alley a woman struggling / grappling with an unsavory looking guy. She screams "Help, he has a gun, he's trying to kidnap me!" Citizen draws a firearm and aims at the unsavory guy and orders him to stop what he's doing. Much additional chaos ensues for a bit . . . and at the end of the encounter citizen is cuffed and taken for booking on a variety of charges for drawing a firearm and pointing it at an undercover cop making a legitimate arrest. In some jurisdictions this citizen is really, really screwed, notwithstanding the fact that he was operating under misinformation and with good intentions.
Again I'll plug Branca's book, or Ayoob's earlier work "In the Gravest Extreme." Branca got started in self-defense law (in his own explanation) after taking Ayoob's LFI course and Ayoob wrote the foreward to the 3rd edition of Branca's book I linked to above. There are some pretty fascinating nuances around self-defense law and I think it worthwhile for anyone who owns a firearm that might be used in a SD situation to understand not just the peril they might be in in a situation calling for the use of force, but the peril they might be in immediately following a decision to use force in self-defense.
