Red-light cameras

The recent article touting the dramatic decrease in the number of accidents at camera equipped intersections is potentially misleading (2/21, A1, "Picturing safer streets; Fewer crashes -- in some cases, far fewer -- are occurring at most KC intersections that have red-light cameras"). The tone of the article suggests the reported positive outcomes can be attributed solely to the presence of cameras.

The analysis was silent on several important questions. Firstly, what was the change in accident rates at intersections where red-light cameras were not installed? Secondly, what was the volume of traffic before and after the installation of red-light cameras? Reporting the number of accidents, as opposed to the number of accidents as a percentage of traffic volume, runs the risk of distorting the real effect of red-light cameras.

Thirdly, what role did the weather, the economy or road construction have, if any, in the reported change in accident rates? Finally, can we confidently assume that the duration of the yellow light at those intersections with cameras has remained unchanged?

I’m glad the number of accidents is down, however, I’m hesitant to agree with Dr. G. David Dixon’s call (2/28, Letters) to "bring on the cameras" until we carry out a more robust and scientific analysis of the data.

For the record, I have not been caught by a red-light camera -- yet.

Richard G. Bradford

Kansas City

Comments

[Keith Williams3]

I have been cut off at these red-light intersections several times; I doubt they even caught the tags of the car that did it but I recieved a ticket in the mail because I had to come to a screaching halt in the milddle of the street. I fought it and won but still doesnt seem lik its making a differnece. I bet half of them are not even working.

[Gary]

Richard, you're not getting it. "Studies" are done by activists and newspapers (but I repeat myself) to justify things that are otherwise not justifiable, and are not intended to be objective analyses. Don't look too closely or think too hard about the methodology. Just go along.