The introduction of automated cameras that ticket people who run a red light has given some cities a "clever" idea – let’s reduce the yellow-light period and increase ticket revenue. Here’s one example from Dallas.
An investigation by KDFW-TV, a local TV station, found that of the ten
cameras that issued the greatest number of tickets in the city, seven
were located at intersections where the yellow duration is shorter than
the bare minimum recommended by the Texas Department of Transportation
The city’s second highest revenue producing camera, for example, was
located at the intersection of Greenville Avenue and Mockingbird Lane.
It issued 9407 tickets worth $705,525 between January 1 and August 31,
2007. At the intersections on Greenville Avenue leading up to the
camera intersection, however, yellows are at least 3.5 or 4.0 seconds
in duration, but the ticket-producing intersection’s yellow stands at
just 3.15 seconds. That is 0.35 seconds shorter than TxDOT’s
recommended bare minimum.