A total of 4390 red light camera tickets, worth $439,000, will be refunded in Philadelphia, Pennsylvania after a ticket challenge revealed that they were improperly issued. The Philadelphia Inquirer newspaper uncovered the error while investigating the case of Mike Kochkodin, 59, who received a ticket on March 17 for allegedly entering an intersection two-tenths of a second after the light turned red. Last month, a Philadelphia Parking Authority (PPA) adjudicator summarily dismissed Kochkodin's case, noting that the city had promised not to take photos until a third of a second had elapsed. After an article appeared on Thursday, PPA decided to refund the tickets.

"We did not know the magnitude of the problem, nor did the contractor report it," PPA Executive Director Vince Fenerty told the Inquirer. "Should we have looked further? Most definitely. We didn't."

Fenerty suggested the error was caused by the February switch from cameras that use 35mm film to fully digital camera technology. The contractor, American Traffic Solutions (ATS), is accustomed to using the quicker trigger setting to maximize the number of tickets issued and was unaware of the 0.33 second requirement. Shorter trigger settings or "grace periods" allow jurisdictions to collect more revenue because the greatest number of technical violations occur within the first 0.25 seconds after a light turns red, according to a Texas Transportation Institute study. Ticketing such violations has little impact on safety as the same study showed the probability of a right-angle collision within a split-second after a signal changes from yellow to red is almost zero at an intersection with a protected left turn lane. "Given a 1.0-second all-red interval, the probabilities also suggest that crossing through vehicles will not start to enter until after about 4 seconds have lapsed," the Texas study explained (page 99).

Philadelphia also seems unaware of its own ordinance, which bans the use of digital technology.

"Photographs collected as part of the automated red light enforcement system must be 35-millimeter film only, must only record traffic violations and may not be used for any other surveillance purposes," Philadelphia Code 12-3012 states.

The provision was initially authored by state lawmakers as a means of ensuring the lucrative contract landed with campaign donor Affiliated Computer Services (ACS). Once the provision was publicized, however, PPA selected a less controversial vendor. Between April 1, 2007 and March 31, 2008, the system issued 89,156 tickets worth $8,915,600 at just ten intersections. Of this amount, ATS took $2,835,952, while ACS took $134,232 for collection services.