After failing to change the City regime, he declared he was trying to be elected for mayor to do what he wasn't able to do in the Riots.
Pope was a good friend of Faith's (and her sister Kate Connors) family, who helped him out on organizing and planning the Riots. After the Riots stopped, he still didn't give up hope of ending such a different government. So, he wanted people to elect him for mayor at the game's present tense. Then, he found out about Project Icarus and the Pursuit cops. Trying to spread the truth about the secret project, he was killed by Celeste, who at the time did not tell anyone she was working with Callaghan, or at least working with people that was helping the current mayor. Before his death, though, he managed to call Kate Connors to his office, where he was shot by Celeste (with Kate's pistol to frame her). Although all evidence of him knowing Icarus was gone, he still held a piece of paper that said "Icarus" on it. That paper was given to Faith in Flight.