#e54

For Earth 54 it's specifically because of the original Joker. At first it was no worse than any other city impacted by the great depression, ridden with crime due to prohibition empowering the mobs, and a police force on the mob payroll.

But when costumes heroes and villains began popping up (at a normal rate initially), one mobster realized that things were going to change. He became The Joker and decided to make it his life's mission to destroy the old mobs and replace them with what he saw as the future; costumed criminals dedicated to chaos and mayhem. He and his Wonderland Gang (with notable high ranking members being the original Mad Hatter, Carpenter, and Ventriloquist) laid the seeds for Gotham's later chaos.

On the flipside, because it isn't supernatural in nature, it's a solvable issue. Bruce spends his life making the city actually better, and after retiring in the wake of Joe Chill turning himself in in the 80s, Arkham is reopened as the Martha Wayne Home, which provides actual proper care for people impacted by Joker's legacy.

This is so funny

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