Gil Mason once served as Deputy Police Commissioner under
Tim Matheson the voice of Gil Mason
James Gordon. He eventually took the job himself when Gordon was thrown in jail for accepting bribes from Rupert Thorne. However, unknown to Gordon and everyone else at the time Mason was placed in the police department by Two-Face, first as his assistant then rising to the rank of Deputy Commissioner. This was done in order for Two-Face to take control of the police department. When Gil Mason first came onto the force he was a highly skilled officer and Gordon thought of him as a godsend. During his tenure at the police department Mason helped bring down Rupert Thorne and other crime lords in Gotham. Much of this was done by using information from a mysterious informant (who was obviously Two-Face). Gil started to have feelings for Barbara Gordon and she began to return those feelings until she learned that Mason committed several crimes, including framing her father. After Gordon's arrest Mason became the new police commissioner. He appeared to support Gordon's bid for bail which had been denied by the courts, and appeared at a public rally for him. At the rally Two-Face staged an event that allowed Dick Grayson to discover his true nature. As Two-Face's men drove by they shot at the stage where Mason was giving his speech. However, when Dick watched the news footage of the shooting he noticed that Mason took cover before the hitmen drew their guns. When Batman refused to help her father (he was investigating but not the way Barbara wanted) Barbara did her own research and discovered the man that shot at Mason. Barbara Gordon rushed over to Mason's apartment to tell him, only to discover the hitman was in his livingroom. At that moment Barbara learned that Mason was involved with her fathers framing. Realizing there was no one she could trust Barbara became Batgirl. When Mason went to identifiy a criminal named Matches Malone, Robin and Batgirl followed him. After Batgirl saved her father on a pier Mason got in a speed boat and drove away. However, Batgirl followed him. While on the boat Batgirl and Mason fought. When Mason gained the upper hand and removed Batgirl's mask revealing it to be Barbara. After this Mason expressed surprise that Batgirl was really Barbara. Batgirl then kicked Mason and he fell and hit his head which made him go into a coma. Despite his injuries Mason was indicted for his crimes. It is unknown if he recovered from his coma, or if he remembers Batgirl's identity.