Chicago hearing officers have invalidated more red-light tickets because of short yellow light times under the photo enforcement program's current operator than when the city's previous vendor was in charge, a Chicago Tribune investigation revealed. 

 Xerox State & Local Solutions became the city's red-light camera operator in March. Before that, Redflex Traffic Systems Inc. managed the program. The city fired Redflex as its vendor in 2013 due to a bribery scandal.

The city requires a yellow light signal length of at least 3 seconds.

Of the 1,500 nullified red-light tickets since April under Xerox, hearing officers tossed more than 200 of them because yellow light times were under three seconds. By comparison, just 37 out of more than 12,000 rejected red-light tickets over a four-year period under Redflex were invalidated by hearing officers due to short yellow lights.

"I am getting 60 to 70 percent of my Xerox photos that come up, they are under 3 (seconds)," Robert Sussmans, an administrative law judge, said at an August hearing. "When the city starts getting this stuff right, I will start finding liability again like I was doing before. But right now, I just can't do it until the city becomes more reliable. … Something is going on here. I mean this has to be taken care of."

The city's Transportation Commissioner Rebekah Scheinfeld maintains that electrical power issues can cause yellow light times to vary slightly. She stressed that the yellow light times are within the "allowable variance." 

"It's showing 2.9, it records 2.9 on the data bar as you see on the violation," said told the newspaper. "But that actual performance is probably 2.998 — or something like that — where the variation is in the hundredths or thousandths of a second, which is imperceptible."

On the tickets themselves, yellow light times are shown as a tenth of a second shorter, she said. That decision by Xerox to slightly shorten yellow light times on tickets "is all well within the national standard for any type of allowable variance."

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