DA Harvey Dent had recently been elected and vowed to bring the wave of crime to a halt by getting gangster Carl Grissom in court and convicted.
In the earlier drafts of the script, Harvey Dent was set to appear in Batman Returns, played by Billy Dee Williams. He was going to be used in the Max Shreck role, and the scarring of his face (which would turn him into the villain Two-Face) was set to happen during the finale when Catwoman kisses him while holding onto the Penguin's generator. (This would then, in turn set up the third movie, in which Two-Face was going to appear as the main villain.)
After the recent death of Max Shreck, Gotham Globe Publisher Harrison Provost became the new head of the Gotham underworld which worried Commissioner Gordon since he cited that Provost was too wild to lead the underworld and that Grissom was better in doing it. Harvey tried so hard to deal with Maroni and the mysterious Riddler who has been killing people. Provost had his moll Candace steal Harvey's medical records and called him over to Axis Chemicals where the Joker was born. Provost attempted to use Harvey's alternate personality Big Bad Harv to control him, however Big Bad Harv started to take over and that led confrontation led to an explosion horribly damaging half of Harvey's face and making him into the gangster Two-Face. Two-Face then formed an alliance with the Riddler after killing Provost in his office and to get revenge on Batman for failing to save him and Gordon since the GCPD were shooting at him by mistake at Axis Chemicals.