Gillian B. Loeb

As much politician as policeman, Gillian Loeb was a blight on Gotham. He ran the city like a criminal kingpin and the police under his command were used as his personal enforcers. He was particularly close with Lieutenant Branden and his shoot-first SWAT teams. Under Loeb's watch, the city experienced relative peace between the various crime families. That peace allowed them to exploit and extort the citizens who lived and worked on their turf. As long as Loeb remained in power, so too would the kingpins.

Before Arkham Origins Incident
Gillian Loeb was the corrupt Police Commissioner of Gotham City who succeeded Jack Grogan. He was known to have ties with Black Mask and Carmine Falcone. After Batman had interfered with Falcone's and Black Mask's businesses, Loeb told Gordon to find and arrest the vigilante.

Arkham Origins Incident
Loeb had ties with the crime lord, Black Mask, and ran operations with Sionis in consideration. He once tried to have the police make false accusations of then-Captain Gordon, but when those fell through, he considered having Gordon murdered, although Black Mask was able to talk him out of it, and said that Gordon was "good PR" for the department. Eventually, he had Harvey Bullock try to dig up any dirt on Gordon, suggesting that Harvey find a woman for Gordon to save and fall into an affair with.

Loeb had a speech conference on Christmas Eve that regarded the impending execution of Julian Day after he was arrested. However, he dismissed any questions from the audience after one of them inquired about the rumors that the GCPD wasn't actually responsible for Day's apprehension, with the implication being that Batman was the one responsible.

That same night, Blackgate Prison was broken into by "Black Mask" and his men, and Loeb was taken hostage. Loeb questioned who he thought was Sionis about his actions. The latter replied that things had changed, and that he was starting over with a new slate: one that Loeb wasn't on. A protesting Loeb was then thrown into the prison's gas chamber, where he died from the poisonous fumes. Loeb's death put Captain Gordon in charge of the GCPD, and the cops were shocked over what happened to Loeb at Blackgate. In reality, Loeb had actually been killed by the Joker, who had taken over Black Mask's operations earlier and posed as the fallen crime lord.

Later the same evening, Loeb appeared in a hallucination suffered by Batman, which was caused by Copperhead's venom. In the hallucination, Loeb blamed Batman for his death, and claimed that he should have saved him.

Cold, Cold Heart Incident
In the Cryptographic Sequencer, the radio broadcast announced to Gotham that Gordon had replaced Gillian Loeb as police Commissioner since Christmas Eve. Also, Loeb was blamed for the police corruption that he tied with Gotham's kingpins for running the organized crime operations.

Commissioner Loeb
Real Name: Gillian Leob

Batman's Database Profile
As much politician as policeman, Gillian Loeb is a blight on Gotham. He runs the city like a kingpin, and the police under his command are used as his personal enforcers. He is particularly close with Lieutenant Branden and his shoot-first SWAT team. The city has experienced relative peace between crime families. This peace that has allowed them to exploit and extort the citizens who live and work on their turf. As long as Loeb remains in power, so too will the kingpins.

Trivia

 * Unlike his comics' counterpart, Loeb was not killed by the Hangman after he was replaced by Gordon, but by the Joker who posed as Black Mask when he was still Commissioner.
 * When Batman examined Loeb's body after he died, one could notice that Loeb was laying face-up on the floor with his head pointing at the door. That was impossible, since Loeb was supposed to be laying face-down in a different position, if you compared it to how he fell to the floor when he died.
 * The late Jon Polito, Gillian B. Loeb's voice actor, had previously voiced Loeb in the animated adaptation of Batman: Year One.
 * Loeb was mentioned by one of the street thugs in Batman: Arkham Knight, commenting how one of Loeb's pros was how he could be paid off unlike Gordon. The street thug also makes it clear he is not aware that Loeb has been dead for ten years.
 * In the concept arts for Batman: Arkham Origins, Loeb wears clothes that are strongly reminiscent of the Penguin's clothes. It is unknown if it is intended.
 * It's likely that Loeb's name comes from Jeph Loeb, who was an author on several Batman stories (including The Long Halloween).