The Military's Non-Lethal Weapon Wishlist.

[Mustrum_Ridcully]

The most insidious aspect of less lethal weapons is they can bypass the psychological reluctance to kill. An enforcer called to fire in a situation in a situation of questionable justness will have less reluctance to fire with a weapon that won't likely kill the target. While a less lethal weapon won't change a unlawful order to a lawful order, by taking away the LETHALITY of pulling that trigger, it makes the order more palatable.

Is it? I think that men or women crying in pain causes psychological pressure on yourself as well, even if they were hostile. The dead don't cry or scream.
For law enforcements, if people have plenty of experience or see footage of people suffering from the pain of "non-lethal" weapons, this also causes negative feedback against law enforcement.