It is a bad situation for everyone involved. Even when people do everything right folks can still end up dead. Life is fairly serious and rarely forgiving. When we put deadly weapons into the equation things get less forgiving very quickly.
Every time I walk out the door with a weapon on my belt it is with the understanding that while it may save my life in a violent encounter it may also get me shot by someone (LEO or citizen) that might mistake me for the bad guy.
The only guarantee we have in this life is that it will end eventually. No matter what we do, the time will come. All we can do its hope to delay it a bit.