"These are vehicles used by our gang enforcement units, homicide detectives, narcotics and many other things," Sesso said. "These are all vehicles being used for legitimate law enforcement purposes at the time. Just because they are not marked does not mean they are not emergency vehicles."
That included one unmarked car assigned to the department's bomb squad that has racked up 15 red light tickets, the most of any government vehicle found in the newspaper's review.
"It's the bomb unit, and they respond to reports of bombs, suspicious packages, arson," Sesso said. "Fifteen violations in six years seems reasonable to me. I am sure if you had a suspicious package you'd want them there as fast as possible too."
Police commanders who drive cars that are not exempt, as well as Fire Department personnel driving certain vehicles, can take advantage of an internal appeals process at the city. Since 2007, the Department of Revenue has excused more than 700 tickets for vehicles involved in emergencies or investigations.
Under that process, a converted recreational vehicle that operates as a Fire Department mobile command center was excused from a dozen tickets, said Larry Langford, the department spokesman.
"Look, they don't drive those things around the block for no reason," Langford said. "When they are out, they are on their way to the scene of an emergency."
Langford said the unit that received 12 tickets was often used as a backup when other command units were out of service.
"This unit has large flashing lights on the rear, but in the pictures I checked, the lights were probably between flashes when the camera shutter took the pictures," he said. "Hence the vehicle was flagged as 'running the light."'
Automated traffic enforcement programs have proliferated around the country, with supporters saying they improve safety and free up police resources. Critics argue that the programs are a money grab and question the camera safety records.
Nowhere has the issue been more controversial than in Chicago, where Redflex Traffic Systems Inc. has operated the largest red light camera program in the country. Mayor Rahm Emanuel fired the longtime contractor earlier this year following Tribune reports about the company's close relationship to a city official who oversaw its contract.
The company is now the subject of a federal bribery investigation, and City Hall has selected a new vendor to eventually replace Redflex.