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You should get in touch with the National Motorists’ Association - http://www.motorists.com/ - they’ve been following the red-light camera issue for years.

To wit:

January 14, 2002 - “The most significant change in the number of violations occurred at the intersection of Mission Bay Drive and Grand (1541) where the yellow change interval was extended from 3.1 seconds to 4.7 seconds. This change resulted in an 88-percent decrease in the number of violations. At the five other intersections, the number of violations dropped significantly in response to longer yellow times.”
[”City of San Diego Enforcement System Review Final Report”, PB Farradyne Inc., January 14, 2002, Chapter 6 (Traffic Engineering and Traffic Operations Improvements”, page 78] (there was no public disclosure of the yellow increases when they happened or the results from making them)

Don’t you recall that San Diego was sued and that shortening of yellow intervals was documented and proven in a class-action lawsuit resulting in the cancellation of thousands of tickets and removal of red light cameras?

http://www.thenewspaper.com/news/00/63.asp

4. After the red light program began in San Diego, at least two intersections had their yellow light phases shortened by a full second before the computer-enforcement devices were installed. The intersections were: (1) Grand Avenue and Mission Bay Drive; and (2) Mira Mesa and Scranton Road.

...and...

One of the computer-enforced intersections, the intersection at Grand Avenue and Mission Bay Drive, had citations drop from more than 1,000 per month to less than 50 per month when the yellow light time was increased by 1.7 seconds – from 3.0 seconds to 4.7 seconds – allowing drivers sufficient time to react.

I don't doubt that municipalities have reduced yellow intervals in an attempt to collect more revenue from red light cameras. My point is that I have yet to come across a single case in which a municipality has reduced the length of a yellow phase at any signal to an interval that is less than the interval that is warranted under traffic engineering standards for the safe operation of that intersection.

. . . the intersection of Mission Bay Drive and Grand (1541) where the yellow change interval was extended from 3.1 seconds to 4.7 seconds. This change resulted in an 88-percent decrease in the number of violations. At the five other intersections, the number of violations dropped significantly in response to longer yellow times.

This isn't exactly a huge surprise. Reporting a decline in red-light violations after an increase in the yellow intervals at an intersection from 3.1 to 4.7 secinds is sort of like reporting a decline in drunk driving arrests after an increase in the legal BAC limit from 0.08% to 0.12%. The number of violations has declined because the definition of a violation has changed!

The question is: What SHOULD the length of the yellow interval at that intersection be?

I have no evidence to support this other than my own professional experience in this field, but there is no question in my mind that the single biggest factor in red-light violations at an intersection is THE EXCESSIVE SPEED OF MOTORISTS on the intersecting roadways. If a roadway has a posted speed of 35 miles per hour, the signal timing plans for its signalized intersections are going to be designed based on that speed. This means that anyone driving faster than that posted speed -- even just a little faster (say, 40 miles per hour) -- will face potential situations in which the length of the yellow interval will seem insufficient for a motorist approaching the intersection. A higher travel speed introduces an element -- called the "dilemma zone" in traffic engineering -- that involves a brief moment of uncertainty on the part of a motorist approaching a traffic signal just as the indicator turns from green to yellow (i.e., should I try to beat the light or should I brake hard to stop in time?).