At the risk of beating a dead horse, this essay from The Smirking Chimp on the use of tasers is worth the read.

Rather than lowering the level of violence necessary to subdue dangerous individuals, the stun-gun has lowered the threshold of excusable police violence by making the use of brutal force seem protective. . . .

Briefly shocking someone, the story goes, is better than shooting him. But before that choice between two brutalities, there was a choice between brutality and reason -- between Rambo with a shield and good policing. A cop who'd never dream of unholstering a firearm against a lout or a big-mouthed student isn't hesitating to unholster the stun gun and use it repeatedly under the guise of restoring control.