Outside the context of armed conflict, government agents — and the rest of us — can permissibly use lethal force in self-defense or defense of others.
Wait one. Is this the same ACLU that does not support the Second Amendment? If according to the ACLU we do not have the Right To Keep and Bear Arms, How are we supposed to defend ourselves? Exhaling bad breath and cussing out loud?
And then they complain when we do not take them seriously.