JT Wicker

Officer JT Wicker was a crooked GCPD officer who acted as a mole for the Riddler during the events of Batman: Arkham Knight.

History
At some point, Wicker came into contact and became an ally to the Riddler. Most of his jobs involved reporting to Riddler regarding whether Commissioner Gordon was picking up his trail, as well as leaving various Riddler Trophies across Bleake Island.

During the events of Scarecrow's threat against Gotham City, Batman deduced Officer JT Wicker's ties to Riddler and interrogated him. Although Wicker claimed that Batman was going crazy with some guards agreeing, he eventually fessed up, which resulted in Batman throwing him into a cell, implying that his association with Riddler meant that he was no longer a cop. Wicker then tried to protest that he was actually a triple agent, but to no avail.

Trivia

 * He appears to be aware of the Riddler's declining mental health. Wicker noted Riddler's rants, when he was arrested, were amusing at first; however, by the time of Knight, Riddler had stopped caring about himself, which Wicker blames on Batman.
 * Because of him being found at the GCPD Building, where Batman didn't actually fight anyone, Wicker was the only Riddler Thug to not be required to be beaten up and then interrogated. Instead, the player merely needed to approach him and press the counter button to interrogate him.
 * Wicker was one of the few villains to get their own cell, along with Harley Quinn, Officer Owens (temporarily), Killer Croc, Mad Hatter, Ra's al Ghul (if not killed and while "Dead") and Hush (not at GCPD). This was presumably for his own protection.
 * Given that Edward Nigma was originally Head of the Gotham City Police Department Cyber Crimes Unit, it is possible that they where colleagues at that time or at the very least became acquainted with one another during that time. Then at some point after Nigma left the GCPD and became The Riddler, Wicker began working under The Riddler as an informant inside the GCPD. It is also possible that he worked with Nigma during Arkham Origins but was never suspected or caught. Given the GCPD's long history of corruption, either of these could be possible.