Throughout its first season, Batwoman gradually gave us more info about Batman’s crime-fighting career. Perhaps the biggest shock, though – other than Hush taking Bruce Wayne’s face in the finale – was the reveal that the Arrowverse’s Dark Knight had actually killed the Joker. As Luke Fox explained to a shocked Kate Kane, Batman finally snapped and murdered his long-time nemesis sometime before he left Gotham five years ago.
That’s all we know at present, so we’re left to imagine what sort of scenario pushed the vigilante to take a life. A good suggestion would be a version of the Death in the Family storyline, in which Joker brutally beats Jason Todd to death. In the comics, though, Bruce is able to stop himself from crossing that line even after this terrible tragedy. There must be more to it, then. And maybe there is. In fact, maybe it’s already been hinted at by Lucius Fox himself. Or at least, his journal.
In episode 19, Lucius’ lost journal is uncovered and we get to glimpse a passage of it, which reveals that Azrael exists in the Arrowverse, as does his mystical armor the Suit of Sorrows, which is known to corrupt anyone who wears it who’s not pure of heart. In his journal, Lucius reveals that Bruce wore the Suit for a time and experienced “an aggressive behavior” during this period. It’s not stated in the journal, but was the mystical influence of the Suit of Sorrows perhaps the reason that Batman killed the Joker? Maybe.
This is a convincing theory pulled together by ScreenRant, and we’re certainly able to infer from what we know that his murder of the Joker is what caused Bruce to give up the mantle of Gotham’s protector and go AWOL. If his actions were the cause of the Suit of Sorrows though, it’s tragic that he still blamed himself to the extent of leaving behind the city he cares so much about.
Batwoman returns for its second season – with a new lead – in January 2021.