Many antagonists have come and gone throughout over two hundred episodes of Chicago P.D. Few of them, however, can compare to the wicked Brian Kelton. Kelton was a notorious villain during his time on the show and inspired hatred from many viewers because he was so immoral and power-hungry. The despised character had a strong impact on the show, which continued to affect the story even after his death.

Kelton was played by John C. McGinley in Season 6 of the NBC police procedural. McGinley managed to bring to life a truly malicious figure and delivered one of the show's more memorable performances. But who was Brian Kelton, and which character killed him?

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Who Was Brian Kelton on Chicago P.D.?

Chicago P.D.'s Brian Kelton (John C. McGinley) and Hank Voight (Jason Beghe) stand side by side

Brian Kelton was introduced in Season 6, Episode 5, "Fathers and Sons," as an established politician who was running for mayor of Chicago. To the public, Kelton seemed like a charismatic and intelligent leader who guaranteed that he would bring change to Chicago. In reality, Kelton had ties to organized crime that the Intelligence Unit, led by Police Superintendent Hank Voight, managed to uncover. It turns out that Kelton had received illegal campaign contributions from a drug cartel in exchange for the promise that the cartel would be protected if he was elected as mayor.

This discovery led the Intelligence Unit to investigate Kelter's crimes, which became a major plot point of Season 6. The Intelligence Unit faced many challenges throughout this process, such as being followed and attacked by the cartel working with Kelton. At one point, the beloved Officer Kevin Atwater was kidnapped and tortured by the cartel in an attempt to make him stop the investigation. Kelton led the Intelligence Unit down a dangerous path, and bringing him to justice became an all-consuming task for the team.

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Who Killed Kelton - And Why They Did It

Chicago P.D.'s Brian Kelton played by John C. McGinley stands in an alleyway

While Chicago P.D. is no stranger to shocking season finales, the one that saw the end of Brian Kelton was particularly so. In the Season 6 finale, none other than Hank Voight was arrested for the murder of Brian Kelton, who had been found dead in his office the night of the election. However, in Season 7, the Intelligence Unit set its sights on proving Voight's innocence, who maintained that he had been framed. They eventually uncovered evidence that led them to Ray Price, a woman who was a member of the crime organization Kelton had been tied to.

Ray Price killed Brian Kelton as a means of exacting revenge upon him. She had been a powerful leader within the cartel before Kelton organized her removal, betraying her in the process. When Price saw the chance to take her revenge she decided to frame Voight to protect herself. Price was aware Voight had a known vendetta against Kelton and would therefore have a motive for his murder, but Price could not have predicted how tirelessly the Intelligence Unit would work to save its leader.

The storyline involving Brian Kelton on Chicago P.D. highlighted the corruption of all too many politicians who value power over progress. It was a compelling depiction of the power struggles that occur in the world of law enforcement and politics. It also showcased the Intelligence Unit's commitment to justice, even in the face of powerful enemies. Even though Kelton's arc took place within one season, he has remained one of Chicago P.D.'s most troublesome villains.

Chicago P.D. airs new episodes Wednesdays on NBC.