July 24, 2014 at 9:25 AM

Chicago officials will review more than 9,000 red-light traffic tickets issued during questionable increases in camera activity, according to the Chicago Tribune. At the center of the issue is Redflex Traffic Systems, the Arizona-based firm that ran the program involved in a corruption scandal.

Chicago's review comes after the Tribune examined 4 million tickets issued since 2007, finding unexplained spikes in the writing of tickets, caused by malfunctioning equipment, human intervention or both.