New Mexico State University (NMSU) researchers have updated their analysis of the effectiveness of red light cameras in Las Cruces. Despite their best efforts, the results of the interim study presented to the city council Monday failed to find any clear and convincing evidence that the red light camera program that began in March 2009 has had a beneficial impact on safety.

The analysis looked at the four original photo enforced intersections and compared their performance to six camera-free intersections that served as a control. The data covered three years prior to enforcement and three years following, with the numbers controlled for the volume of traffic. The researchers concluded accidents decreased at one intersection and increased at three others. Overall, the statistical analysis showed a negative impact to the program.

"There was an overall increase in crash rates with contributions from three of the four camera intersections (i.e., Lohman and Walnut; Main and Solano; and Valley and Avenida de Mesilla) showing significant increase (i.e., negative impact) while the Lohman and Telshor camera intersection showed a significant decrease (i.e., positive impact)," the study found.

Though camera advocates claim their goal is to reduce violations, the data in Las Cruces show the number of violations recorded either remained flat or, at two intersections, actually increased.

"Red-light violation did not decrease in any of eight camera sites since starting the STOP program," the report explained.

The negative findings did not deter the city council which remained unanimous in their support for the program that has dealt out $3,816,900 in fines. Several councillors at a work session Monday grasped for anything they might use to explain away the statistically significant increase in crashes.

"Did Best Buy have more sales on big screen TVs?" asked city councilman Greg Z. Smith on Monday. "I do think those pieces of information might help us... if there was more retail activity at this location."

Councillor Gill M. Sorg reached for another interpretation.

"If there's something distracting drivers -- flags waving or a flashing light -- I think we have to take that into consideration, too," Sorg said.

Redflex Traffic Systems of Australia mailed out 38,169 red light camera tickets in three years, with citations going to vehicles photographed entering an intersection as little as 0.1 seconds after the light changes from yellow to red. The majority, 56 percent, of the tickets were issued for split-second violations which the report suggested could be due to short yellow warning times at intersections.

"The influence of the 'dilemma zone' is probably one of the major reasons for such a high percentage of the red light violations," the report explained. "A combination of shorter signal timing cycle and high traffic volume might have created many dilemma zones that caused indecisive drivers to violate the red light."

Though some tickets were issued for entering 3 or more seconds after the light turned red, these violations were seen primarily at the intersection of Valley and Avenida de Mesilla, which issued 81 percent of its tickets to cars that made rolling right-hand turns. Late entry on red is dangerous in a straight-through violation, but boulevard stops, whether late or early, are not a significant cause of accidents (view study). At the intersections that did not issue right-turn on red tickets, 67 to 74 percent of the citations were for highly technical, split-second infractions.

NMSU will continue to collect data and put out further updates on the report. A copy of the report is available in a 1.5mb PDF file at the source link below.