I have to agree with Whirli on this one. Warning shots are dangerous both legally and tactically. My CHL instructor summed it up pretty well when he said every bullet had a lawyer attached to it ready to sue you. My opinion is they got their warning when they passed the no trespassing sign. Warning shot also indicate location. If I am outnumbered I want the element of surprise on my side. The other thing is, in SHTF, warning shot is more than likely going to guarantee return fire. I want to be reducing the number of incoming rounds each time I squeeze the trigger. The moral standpoint is one you have to decide for yourself before this scenario takes place. Trying to solve a moral dilemma in the moment might get you or someo you love killed.