Abstract
Photo-red enforcement has generated media scrutiny for agencies maintaining these cameras as well as the affiliated private-sector companies who provide related equipment or services. In response, some jurisdictions are interested in evaluating the effectiveness of their photo-red enforcement programs. This article illustrates the effect that 2 aspects can have on such an evaluation: 1) a change (yellow) interval based on the prevailing speed as opposed to the speed limit and 2) the temporal distribution of red-light violations. (Author/Publisher)