Geoff Shancoe was a good cop and a newlywed working for Gotham Police Department when he was involved with charging the Joker after his first apprehension and arrest. The Joker, abusing his right to a phone call, phoned Geoff's wife and convinced her to kill herself.
Following the suicide of his wife, Geoff turned back to alcohol and watched as the Joker spread more mayhem and murder from incarceration. Geoff eventually decided to take matters into his own hands. Shooting both Jim Gordon and his own partner, Geoff then intercepted the Joker's prison transport. Instead of killing Joker, he was using the entire thing as bait to draw out Batman - his true target - for having delivered the Joker to the police in the first place.
Geoff's attempt to hang Batman failed and he was sentenced to imprisonment in Arkham Asylum... in the cell right next door to the Joker.
Geoff Shancoe was created by Andrew Kreisberg and Scott McDaniel and first appeared in Batman Confidential #22. Geoff first appeared as Bad Cop in Batman Confidential #29 also by Kreisberg and McDaniel.
Major Story Arcs
While imprisoned next to the Joker, the Joker drove Shancoe over the edge and eventually was convinced to become the Bad Cop by Joker himself who also helped Shancoe escape.
Bad Cop went on a shooting rampage at Gotham Police Academy where he killed several recruits and wounded a young Renee Montoya. Both Batman and Shancoe's former partner (now confined to a wheelchair due to being shot by Shancoe earlier) arrived on the scene and attempted to place Bad Cop under arrest. Begging for his partner to just shoot him, when it became clear that his death wish would not be granted, Bad Cop made an escape.
Next choosing to try and tempt Jim Gordon to shoot him, he arrived at an arcade where Gordon was spending the evening with his daughter Barbara Gordon. Threatening to kill Barbara, Bad Cop insisted that Gordon would have to kill him or lose his daughter. Barbara tricked Bad Cop using a fake gun from an arcade game and stalled him until Batman arrived and Bad Cop was arrested.
However, the entire Bad Cop attack was a diversion created by the Joker to escape from Arkham Asylum himself.