The Warning Shot: Is it Necessary?
We all see in the movies how the good guy confronts the bad guy (especially westerns) and shouts, "stop hand up!" and fires in the air a warning shot. Depending on the script, the bad guy either desists and raises his hands, or fights back and gets gunned down by the good guy. Police call the warning a "challenge", which usually takes the form of a word "Freeze!", with the cop pointing his gun at the criminal. The challenge is usually made to de-escalate the situation and give the criminal an opportunity to give up.
But in real life, is the warning really necessary?
Ans: Not recommended.
A civilian (and LEO) is justified to use deadly force only if there is imminent threat to his life of possible grave bodily harm or injury. The word "iimminent" means IMMEDIATE; the threat is right there right now. In such case, you are fully justified to neutralize the pepetrator. If you have time to shout a verbal warning or a warning shot, then logically the threat is NOT imminent yet. So there is not justification to shoot yet at that point.
Likewise, shouting to wound is a misnomer. In real life a bullet to any part of the body is quite likely to maim or cripple for life, if not kill. The effects of a bullet wound, even if not immediately fatal, can drastically shorten the natural life span. Remember, even if the person shot survives but dies a year later from complications, it's the same as if you killed him outright. Your gunshot is still the proximate cause of his death.
For civilians, the sight of a gun is, and should be, warning enough for the criminal to desist. Also, if there is the distinct possibility that if the criminal turns and fires back, and the good guy is not fast enough, he may be the one to get killed instead of the criminal. This goes true especially for home invasions. If you confront a robber or a burglar in your house and he has a weapon visble or you have reason to believe that he is armed, shoot him immediately, in back if you have to. That may sound brutal, but in court a home invasion is almost always defensible.
Lastly, a warning shot fired into the air can travel a mile and kill an innocent child a block away. Guess who's responsible? As we learn every year during new year's eve, stray bullets are not always that stray and are not so harmless as we think. By the law of physics, a bullet fired upwards has the same velocity as when it left the barrel, when it comes down and hits the ground.
Remember: the only time you wil ever be justified to fire a bullet into a another human being is when you feel totally justified by every law of God and man to end his life. If you have to give a warning, then you are not justified to shoot him in the first place.