Green Arrow's 10 Greatest Failures

The comics of the Injustice universe focus on the years immediately following the tragic murder of Lois Lane by a drugged Superman, cataloging every attempt by Batman's resistance to prevent the complete global takeover by the Man of Steel.

In the first year of the Injustice storyline, almost immediately after the Joker's murder, Oliver Queen tracks down and arrests Harley Quinn, who was able to escape since all attention was on her clown prince. Harley's arrest is difficult, but eventually, she is taken to Arkham Asylum for both her and Oliver's safety.

Yet right as Ollie brings Harley into the Asylum, several other heroes are there fighting over whether or not Superman should be allowed to mercilessly slaughter every single inmate. The self-proclaimed social justice warrior leaves Harley alone with a single guard to try and diffuse the situation. Harley, of course, immediately escapes from her cuffs and decides to spring all of her crazy criminal compatriots.

During the ensuing chaos, Nightwing is accidentally killed by Robin and most of Arkhams patients escape to cause even more mayhem for Superman and the innocents of Gotham.

So in a very indirect way, Green Arrow caused Nightwing's death, and the escape of nearly every Arkham Asylum patient simply because he couldn't lock Harley in a cell before offering his opinions. Something even Batman remarks to the emerald archer during that storyline.