Incentives matter: red-light camera file 2

Alex Tabarrok at Marginal Revolution points out that, Incentives are everywhere. His example is

[t]he 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 (TxDOT).

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.

For more on incentive effects of red light cameras see my previous posting, Incentives matter: red-light camera file. Here I point out that red light cameras provide no real safety benefits but do provide revenues, at least until drivers change their behaviour because of them. But now it appears city authorities can change their behaviour to.