James Wheeler is an Assistant District Attorney, and Diane Hansen's ex-boyfriend and co-counsellor.
After the framing of Lawrence Pope by Diane Hansen's ring, Wheeler started to suspect Hansen's involvement in the crime. He attempted to meet with her privately, and even broke into her office to print details regarding Pope's younger brother, Michael Pope, who was the only witness to the crime his brother was framed for. ("Pilot")
Following Lawrence Pope's murder, Hansen tasked Stills and his men to murder Wheeler. Bringing along an ex-con Wheeler put away to frame for the murder, Stills was notified that Wheeler's son was with him. John Reese, who at first believed Hansen was in danger yet later learned of Wheeler's upcoming attack, intervened and held one of Stills' men hostage. Wheeler and his son left the building with no knowledge of their intended murder. ("Pilot")
In court the next day, Reese planted a recording of Hansen ordering Stills to "take care of Wheeler," with the entire court, including Wheeler, learning of her true nature. ("Pilot")