When was this introducted, I think actually it was a work in progress it was added little by little over the course of UO's history. I know that you can gain in justice by killing murderers, and there are specific uses when you have enough of the virtue, like sacrifice for example.
Yes, Sacrifice is implemented here for uber-powerful templates to insta-res and all kill you, because they 'sacrificed' so much. /wrists I'm not sure when each were implemented but Justice was established in 2002 with Publish 16.
