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Incentives are everywhere
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 (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.
More examples here and a hat tip to J-Walk Blog.
Posted by Alex Tabarrok on April 10, 2008 at 07:10 AM in Economics | Permalink
Comments
But if the article is correct, the cameras were installed at traffic signals that already had short yellow periods.
Posted by: Cyrus at Apr 10, 2008 7:40:42 AM
Those short yellow period lights should have been adjusted to comply with the law and not used as a method of theft by the gub-mint.
Posted by: Chairman Mao at Apr 10, 2008 8:34:25 AM
there's this one part, in office space, when michael bolton finds out that he's going to be fired. He refers to the people firing him (lumberg, et al.) as "---- gobblers."
That's all I have to say.
Posted by: shawn at Apr 10, 2008 8:45:19 AM
This is entrapment, and a class action lawsuit against the city should ensue. It's made all-the-more egregious by the use of a non-conforming yellow light length.
Posted by: Colin at Apr 10, 2008 8:50:23 AM
I live literally 5 minutes from that intersection. Greenville is a major nightlife area in Dallas, and the street fills up with cars from about 9 PM to about 2 AM. There have been a large number of wrecks and DUI-related incidents at that intersection, mostly because there is so much traffic people try to slip past even after the light turns red. But that light has always been bad, even before they installed the cameras. Is it probable that shorter yellow light times might lead to more people trying to run it? Yes. Are the shorter yellow light times a conspiracy on the part of cities to increase revenue? Very, very unlikely. Comeon! Is .35 seconds really significant?
Posted by: Jason at Apr 10, 2008 9:06:23 AM
Alex: In some municipalities, not only is the issuance of tickets and collection of fines is performed by the company that installed the red light cameras, but so is the appeal process. Seems to me they have the incentive to deny as many appeals as possible.
Cyrus: The 'political' reason for installing red light cameras is safety. If politicians are really interested in safety, they would direct their Public Works or Traffic department to increase the yellow-light period. However, that would not generate revenue for the municipality (and the company that installs and maintains the cameras).
Posted by: Vincent Clement at Apr 10, 2008 9:13:48 AM
Going 30MPH .35 seconds is about 15 feet.
Posted by: JoshT at Apr 10, 2008 10:25:55 AM
0.35 seconds, and those 15 feet (35MPH = 56.3 fps), are tremendously significant if you are anticipating that you have them to get through the intersection. Remember, driving is mostly a sub-cognative process - you learn that yellows are so long. If there's a policy that they should be no shorter than X, and then there is a light that is 10% shorter than X, the marginal car will not be able to adapt.
Also, at 35 MPH, your total stopping distance is 136 feet, that takes into account the 59 feet of require stopping distance for the vehicle, plus the 77 feet for the reaction time. That 77-foot reaction time is 1.36 seconds. See how that 0.35 seconds comes to play now?
See http://www.csgnetwork.com/stopdistinfo.html for the stopping distance calculations.
Posted by: Colin at Apr 10, 2008 11:09:22 AM
There was a situation recently in Chattanooga where a ticketed motorist managed to prove in court that the yellow-light delay time for a camera he got a ticket from was 3 seconds rather than 4 seconds (which is the standard for other similar cameras). The judge threw out the ticket and ordered the city to refund the fines for all other motorists (176 in total) that had gotten ticketed by the same camera.
I also saw that a Tennessee senator plans to introduce a bill that explicitly requires that the timing of such traffic lights be established by the city engineer, not by someone else (treasurer??). I'm not sure if that bill would be very relevant, though...
Posted by: Scott K at Apr 10, 2008 11:25:10 AM
This should be very easy to resolve. In Texas, any directive to deliberately shorten the timing of these lights should be discoverable through a very simple open records request. All it takes is an email or letter asking for it; probably no, or minimal, cost. Of course, it’s much more fun to simply spout conspiracy theories and whine about revenue grabbing cities.
Here are the contacts if anyone would rather do more than just whine http://www.dallascityhall.com/pwt/contacts.html
Posted by: mike at Apr 10, 2008 12:33:12 PM
Several cities are now removing the cameras due to increase accidents. A study by University of South Florida College of Public Health confirmed that red-light cameras significantly increase crashes and are a ticket to higher auto insurance premiums. More at: http://www.physorg.com/news124467295.html
Posted by: Ron at Apr 10, 2008 1:26:14 PM
West Hollywood does this. The difference b/w City of LA and City of W. Hollywood yellows is significant. The only ticket I've had is from a 2.7 sec yellow in WH.
If the city were interested in safety then it could have the yellow in seconds just as the don't walk signals now have.
Now that I have a new car w/ dealer plates, I'll just keep those on for as long as possible to avoid the potential for these tickets. Going on 6 mos.
Posted by: jdd at Apr 10, 2008 3:47:59 PM
In Spain, a Mayor ordered a survey.He asked if traffic light are giving orders or advices.Most people said : advices.He ordered to get rid of all traffic lights.They were to expensive to be giving advices
Posted by: karl at Apr 10, 2008 3:49:44 PM
I thought that using cameras was unconstitutional. First of all, you're robbed of your due process rights and second, it's hearsay. Obviously I'm wrong, but then, so is the law.
Posted by: Mike Fladlien at Apr 10, 2008 4:33:01 PM
It may well be that the city intentionally set short yellows in order to raise ticket revenue, and/or intentionally concentrated red-light cameras at short-yellow intersections. However, the mere fact that the highest-revenue intersections are usually short-yellows is not evidence of that; even if the short yellows were set decades ago, and the cameras placed, much later, randomly, that is still what you would expect to see.
Posted by: DF at Apr 10, 2008 6:00:42 PM
Radley Balko (The Agitator) has been writing about this for a while. IIRC, he has noted that there are more accidents at intersections with shorter yellows. So here we have a situation where the local government, in order to maximize revenue, has actually increased the likelihood of accidents. A net decrease in public welfare, you could say.
"Remember, driving is mostly a sub-cognative process - you learn that yellows are so long."
I'll second that. A few weeks ago, while approaching an intersection around sunset, I noticed something wrong, but that I couldn't quite put my finger on. Slowing down, I realized that the lights weren't on. Usually, they default to blinking red when the power goes out, but the power all up and down the street was on and no lights. We, like most of the other cars, treated this as a 4-way stop, but we saw several cars just blindly wander through the intersection (accidents were narrowly avoided). We realized that people aren't looking for green, they are looking for the absence of red.
Posted by: Eric H at Apr 11, 2008 9:31:46 AM
I've ocassionlly suspected that municipallities might tweak the timing of lights to induce people to speed and write more tickets.
I don't really think they do this, yet it would be so easy to time the damn lights properly. Why don't they?
Posted by: aaron at Apr 11, 2008 11:17:49 AM
Don't forget, these intersections probably have shorter yellows because of their high traffic volume.
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