DC Comics has had a long and ever changing history with the costumed character called The Vigilante. He started off as a western hero named Greg Saunders (No relation to the character on CSI.). He was then rebooted in the 80's as Adrian Chase, a New York District Attorney. During Chase's time two men Alan Welles and Dave Winston would also wear the mask. The mantle would then be taken up by Patricia Trayce, Justin Powell and finally Dorian Chase.
We're going to narrow our focus only to the Adrian Chase story as that is the version currently popping up on Arrow and also influence all that came after him.
This version of the Vigilante was created by Marv Wolfman and George Perez in New Teen Titans Annual #2. His origin was pretty straight forward. His role as a D.A. put him on someone's hit list and his family got killed because of it. Unlike a similarly origined Punisher, Chase made sure to use non-lethal means for a very long time. It wasn't until the 37th episode of his own series before a police officer died because of Chase's actions. After that the character become more violent and less careful.
By the second issue of the series, Chase was already questioning his choice of taking the law into his own hands. He willingly stepped away from the costume when he became a judge, believing he could do more good from the bench then from behind a mask. The problem was his absence left a void that another judge sought to fill.
Alan Welles became a more violent and aggressive Vigilante, killing petty criminals and anyone else he felt deserved it. Chase got involved and tracked down the new Vigilante, killing him before ever realizing it was his friend and fellow judge. Chase did his best to cover up Welles involvement as the Vigilante while Chase's bailiff next took on the role. Dave Winston refused to kill, banking on the Vigilante's reputation to get what he wanted out of criminals. This worked fine until he was confronted by the Peacemaker during a plane hijacking… a plan Chase was also on. Peacemaker killed Winston. Chase took up the mantle once more and tried to confront Peacemaker, but the out of practice judge was easily defeated and unmasked on television… ruining his life and driving him deeper into the role of Vigilante.
At this point Chase was completely off the rails. Suffering from mood swings that would include uncontrollable rage, paranoia and extreme guilt and remorse. He was out of control, murdering an innocent police officer that got in his way. Eventually it all came to a head in his 50th issue where Adrian Chase committed suicide.
The character was a unique look into the side of vigilantism that doesn't normally get addressed in comics. We see the physical and legal ramifications and even some of the aspects of getting lost in the battle. But here we got to see from the very beginning the toll his actions took on him and that there is no magic wand to erase the guilt that builds up inside. This could be a very powerful story arc to dive into on television, but seems a bit heavy for a B-story. I could see doing this as a Netflix type series from start to finish in 13 episodes focused on his rise and fall. I am curious how far down the rabbit hole the writers will go with this story on Arrow.