Red light cameras - Don't Stop!

Calling your attention to a well-documented history of a red light camera implementation.

by Tom Ferrio

I usually prefer to avoid mention of my time living in Texas. It brings memories of things like our neighborhood sprouting dozens of George Bush for President signs one Sunday morning after church.

But we were there while our town implemented red light cameras and I think the history is informative.


This topic has given us some passionately-felt points of view from Will and Linda.

In this article I give you some excerpts from the extensive report online here. Having lived there during the early years of the implementation my personal experience collaborates with the report - it is not self-serving propaganda by a police state.

The red-light cameras did change behavior, reduced the number of collisions dramatically, and reduced the number of serious injuries at those intersections. Certainly police in squad cars could have been stationed at each of those intersections to have a similar effect but at much higher cost, raising taxes. And police cars chasing after red light runners pose their own danger of collision.

The first part of that report speaks to the legal details and is of less interest to us than the later parts. Note that this implementation was made Redflex Traffic Systems. Other providers would likely work slightly differently.

·        How does the system work?

Each system consists of a series of digital cameras installed near the roadway, including two for the capture of still images and one digital video camera. Utilizing a passive sensor, the system detects when the signal light changes to red. Using digital video presence cameras, the system triggers when a vehicle enters an intersection after the light changes to red. The first digital still camera captures two images (scene A and scene B). Scene A shows the vehicle prior to entering the intersection while the light is red and scene B shows the vehicle in the intersection while the light is red. The photographs display the time, date, and location of the offense, as well as the amount of time the light was red when the image was captured. Also, the speed limit of the roadway and the speed of the vehicle at the time of the violation appear on the photograph. The second digital camera captures a close-up image of the rear license plate of the vehicle. And finally, the digital video captures 12 seconds of video, depicting the 6 seconds prior to and the 6 seconds following the violation. As a result of legislative changes that took effect on September 1, 2007, the Notice of Violation includes only one digital still image of the vehicle’s license plate; however, a link will direct the recipient to a website where the 12-second video and other images can be viewed.

Note that the system is not recording images or video all of the time. I like the fact that such systems are run by a contractor. That puts added barriers in place to prevent a policeman from just watching the video feed for other reasons.

·        How many cameras are in operation and where are they located?

We began enforcement of our program on March 1, 2006 at four intersections, which were carefully selected based on crash data analysis. To date, a total of 14 camera systems have been installed

Prior to those first four installations red-light running was getting worse and worse. If you were the first car stopped at a red light you had to be very careful taking off after the light turned green - look both ways and wait for the people running the light to clear. That didn't happen on every signal change but I would say 1 out of 10 at least. Of course Plano, Texas is a dense suburban community that can have heavy rush-hour traffic. Backed-up traffic at lights contributed to a "to hell with it" attitude, "I'm just one more car going through after the others."

·        Have the Red Light Cameras been Effective?

Since its implementation, the Automated Red Light Camera Enforcement Program has clearly had a positive impact on traffic safety for the citizens of Plano. As indicated in the table below, crashes at the first four monitored intersections decreased significantly from March 1 through December 31, 2006, versus the same period in 2005:

Type	2005	2006	Change
Red Light Violation Crashes	37	25	-32.4 %
Total Intersection Crashes	79	40	-49.4 %

After cameras were installed at those first 4 intersections the newspapers were frequently reporting on the results and the public responded positively to the reduced number of accidents. Obviously our intersections do not have the number of accidents that we see in this example but the speed on Route 1 is much higher and every accident can have a devastating effect. (The cameras in Plano were mostly installed in 40 MPH speed zones and the incidence of speeding is not what we see here.)

Crash Totals for all 13 monitored intersections
YTD January 1 through December 31, 2009 (versus 2005)

TYPE	2005	2009	% CHANGE
Red Light Violation Crashes	140	77	-45.0%
Total Intersection Crashes*	302	157	-48.0%
Rear End Crashes	146	116	-20.5%

"Total Intersection Crashses" include those that involve a red light violation

I have seen some comments about potential red light cameras in Charlestown predicting an increase in rear end collisions so I have included this table.

Here is a map of the area with the camera intersections marked.

You can read more details in the report but I think it is interesting and compelling and avoids the rhetoric around this topic.