A solution to cops killing people who don't have guns Would BE CURARE Darts

The typical complaint by police regarding sedative darts is they don't act fast enough.
Curare does. And there are antidotes.

Dart them back off, cuff and disarm them once they drop then give them the antidote. Also why do the cops just move in on a lone threat so close they have to shoot them. Whats wrong with a margin of distance?

Curare is used in medical anesthesia and very rapidly makes the muscles of the body useless while leaving the heart and lungs more or less functional.