If you like your co-workers then talk them into confronting the boss together. He'll have a hard enough problem replacing one guy and you'll scare the hell out of him if he thinks he may lose more.
I agree with what was stated earlier. Praise should be given publicly and the *****in' should be done one on one. Sometimes other techs and/or my dispatcher will get pissed because they think I should lay into one of the techs but they don't know I already have.....When it's there turn though they appreciate the discretion.