Not sure if the purpose for guys to participate in murders was more to do with making sure there were no undercover cops or informants being inducted or to make them look the most ruthless syndicate?
I think it serves both purposes. The number one purpose is to make sure cops don't get in. No cop is going to commit a murder or seriously injure someone. The second is to make sure you have killers in your crew when the need arises to whack someone.
