Bofh is right about it varying from state to state, but generally-speaking, the standard is state of mind of a "reasonable person" rather than actual, tangible evidence (such as the presence of a weapon by your assailant) for when use of deadly force is authorized. Witness the case of George Zimmerman. FL has a strong Stand Your Ground law. It was determined by the cops the night of the incident that his use of deadly force fell within the parameters of that law, and he was released. After the hoopla arose and the state's AG got involved, Zimmerman's attorneys chose not to go to a SYG hearing, where, had Zimmerman prevailed, there never would've been a trial. The "reasonable person" standard for being in fear for one's life can come from having one's head bashed against a wall or a concrete sidewalk or punched, kicked or stomped just as assuredly as staring down the barrel of a gun can invoke the same reasonable fear. Most states' laws recognize that these calculations are made in the heat of battle and attempt to balance (to one degree or another) between the human instinct for survival against law that provides for public safety. Like Zimmerman, it may take a jury trial to impose which side is weighted more heavily on the balancing scale, but whether it be a decision by the cop on the street or the local prosecutor evaluating pursuing charges or the jury at the end of a trial, the reasonable person standard is always (supposed to be) employed throughout their determination process in every jurisdiction that I've ever looked into in this country.
Bottom line, you will always have to justify the use of a gun as an act of self-defense. If you can't get to self-defense through the reasonable person standard, whatever that means to the people you're trying to justify your actions to, then you're most likely not going to fare too well. In other words, there is no absolute correct answer to your question. And jurisdiction definitely has meaning. In most states, even in 1984,
Bernard Goetz never would've faced trial for the shooting he was involved in, but in NYC, he went to trial for charges ranging from attempted murder at the top, to several weapons charges at the bottom, only one of which of the latter was he convicted on. He spent 8 months of a one-year sentence in prison on that one charge, and was subsequently financially ruined when one of the survivors sued him and won a judgment of $43 million. Shooting someone, even when reasonable people would have done the same thing, is always a crap-shoot. Sometimes you'll win, and sometimes you'll lose, and I am talking about the legal battle that may ensue after the fact, not the battle for your life that you presumably believed you were in at the time of the shooting.
Blues