Harvey Bullock

Harvey Bullock was a detective in the GCPD who worked underneath James Gordon, and, although he was technically corrupt while Gillian B. Loeb was in power, was one of the few comparatively honest cops on the police force.

Before Arkham Origins Incident
Like most of the GCPD, Bullock was corrupt and frequently on the take by various criminal organizations. However, Bullock also refrained from harming civilians, which showed that he had the potential to become a good cop. At some point, then-Commissioner Loeb had ordered for Bullock to get himself in Gordon's good graces (something that Bullock had doubts about, since Gordon didn't trust him, or as he put it "[Gordon] trusts me as far as he can throw me.") and then use that trust to dig up any dirt on Gordon, that also implied that Bullock should arrange a honeypot trap for Gordon.

Arkham Origins Incident
Harvey Bullock was seen alongside Captain Gordon during the incident. He, along the remainder of GCPD, didn't trust Batman. After the Joker was captured by Batman following the Gotham City Royal Hotel Incident, Bullock believed that Batman and Joker were working together, and asked Joker why anyone would throw themselves off a roof just to save him, with Joker also admitting that even he doesn't know.

Later, after Batman brought down Firefly and dismantled 3 of his 4 bombs, Gordon showed shock that Batman had actually brought Firefly down and saved the bridge. Bullock then told Gordon to not give Batman too much credit, and it implied that he still didn't trust him, despite all he that did previously.

After Batman defeated Joker at Blackgate Prison, Bullock contacted Gordon at the Prison Chapel, where Gordon informed him that the Joker was captured. Surprised, Bullock asked Gordon how he caught the Joker, and Gordon told him that he "had some help".

Cold Cold Heart Incident
Because there were still some criminals at large after Joker's takeover of the city on Christmas Harvey Bullock helped the GCPD roundup the other criminals that were still out there after the events. The criminals who were taken down by Batman but left to be taken into police custody. Bullock also helped to remove some corrupt cops from the police force.

Batgirl Begins Incident
After Gordon was appointed Commissioner, the new Mayor Dickerson was determined to counteract the myth of the Batman. As part of his efforts, he tasked certain experts and cops to come up with a practical demonstration on how a normal man could achieve what the Batman could. The display was installed at City Hall. There, Bullock made an introductory speech and concluded by asking if there were any more questions. Just as he was about to unveil the display, an explosion erupted, allowing Killer Moth to make his entrance and take the Commissioner hostage. Bullock ordered all officers present to refrain from shooting, so as to avoid hitting the Commissioner.

The 'Batgirl' then arrived, wearing the suit for the display. She managed to take out Killer Moth's thugs and deduce his identity, which forced him to flee before then being ambushed by the Batman.

After Arkham City Incident
Immediately following the death of the Joker, Harvey Bullock lead a squad of GCPD offiicers into Arkham City. They were then ambushed by forces loyal to Harley Quinn. Thanks to Harvey's quick thinking he was able to knock out Harley Quinn and bring her back to the GCPD. Unfortunately, Harley quickly escaped afterwards. Harvey then reported the situation to Gordon, adding that Harley's forces had ambushed and captured several of their SWAT units that had been sent into Arkham City. Gordon thus ordered him to withdraw them.

Later, a pre-made message from the Joker was triggered, which tricked Batman into going back into the walls of Arkham Asylum, walls which were wired with explosives set to kill the Batman. Upon hearing exposions from the island, Bullock commandeered a Gotham News helicopter accompanied by Vicki Vale. Finding the wrecked Batmobile and a burning Asylum, Harvey came to the conclusion that the Batman had not made it out, which he then relayed to Gordon.

Trivia

 * Robert Costanzo also voiced Harvey Bullock in Batman: The Animated Series.
 * Harvey Bullock bore the likeness of Joe Barbaro, a character in 2k's game Mafia 2, and the man who voiced Harvey was Robert Costanzo.
 * Despite standing at 73 inches tall, in some cutscenes, Bullock looked the same or shorter in height than Gordon, who is one inch shorter.
 * Harvey Bullock's name was seen on a shift list during the events of Batman: Arkham Knight, which indicated that he still worked regularly as a GCPD officer.
 * Bullock being a corrupt cop, but with a conscience is also part of the show Gotham, where he works with Gordon during his early days and is trying to make him conform to the GCPD's methods.
 * Unlike other incarnations of himself, Bullock's obsession with donuts is completely absent.

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