Official Title: Report on the Effectiveness of Automated Red Light Enforcement
This is a 2006 report by the city of Garland Transportation Department on the effects of red-light cameras in the city of Garland, Texas, USA. This study compares the before and after crash statistics of 4 RLC intersections in that city. The study uses 31 months of pre-RLC crash data compared to 31 months of post-RLC data. The statistics used in this analysis are from the Garland Police Department and the study does not define a fixed Distance-From-Intersection inclusion zone for crashes. This study uses crash data for 6 similar intersections in the city as control data. There are no data or conclusions in this report that suggest a reduction or increase in fatalities due to RLCs. The results show that total crashes at RLC-equipped intersections have decreased by almost 25% while total crashes at the control intersections also decreased by almost 10%. Injury crashes have also decreased at RLC intersections by almost 27%. The study concludes that : "Crashes have been significantly reduced in both severity and number as a result of the Safelight Garland Program".
Download this report below (719k)
This is a brief 8 page study, the detail data per intersection per month is not included in this report, even though the violations data per month is included. Also, the selection of 4 RLC intersections is far below average for this kind of study and somewhat diminishes the usefulness of this report. The use of 31 months of pre and post-RLC data is above average for this kind of report and somewhat improves the validity of this report. The lack of a defined crash inclusion zone somewhat diminishes the usefulness of this report, especially due to the fact that several Texas cities use an extremely limited range of 30 feet as their Distance-from-intersection crash inclusion zone(as compared to 150 feet used by the Federal Highway Administration(FHWA)), which severely under-reports the number of rear-end crashes, as evidenced by the Chicago 2010 RLC report. We have asked the city of Garland what they used for a crash inclusion zone, but we have not received a reply. The conclusions are supported by the data that is supplied in this report.