TTI Study Underscores Safety Benefits of Red-Light Cameras

street approaching intersection, sign with 'Red Light Photo Enforced'

Public policy and public opinion don’t necessarily go hand in hand, but when it comes to red-light cameras, two new studies suggest they do. According to the Insurance Institute for Highway Safety (IIHS), most drivers like the cameras. And according to the Texas Transportation Institute (TTI), they work.

The TTI study, although limited to Texas, is one of the most extensive in the nation and focused on the safety aspects of red-light camera use. The primary objective of the study, sponsored by the Texas Department of Transportation, was to evaluate the effectiveness of automated traffic enforcement systems in reducing right-angle, rear-end and other crash types at signal-controlled intersections across the state, and to report the findings surrounding crash incidence at those intersections.

Researchers examined more than 11,000 records of crashes occurring at the 275 intersections statewide where cameras were in place, and compared crash frequencies one, two and three years before and after installation of the cameras.

An overall reduction of 633 crashes recorded at those intersections represents an 11 percent decline. Red-light-related crashes dropped by 25 percent, and right-angle crashes (the most severe type) dropped by 32 percent. The reductions were seen across the board on all types of roadways, including business/primary roads, farm-to-market roads, interstate access roads, state highways and U.S. highways.

Researchers also compared crash frequencies at different intervals before and after cameras were installed. The examination showed a 23 percent drop from one year before to one year after cameras were put into use. The two- and three-year comparisons reflected reductions of 27 percent and 21 percent, respectively.

“These findings show clearly that red-light cameras offer significant safety benefits,” says Troy Walden, the lead researcher on the TTI study. “Most importantly, they help prevent the most severe and deadly type of intersection crashes.”

Publication of Walden’s research comes soon after another study showing that a majority of drivers support the use of the cameras. Focusing on 14 cities in nine states that had red-light camera programs in place, the IIHS found that two-thirds of drivers favored the cameras, and 59 percent believed that the cameras had made intersections safer.

“Most drivers don’t buy the argument that it’s somehow wrong to enforce the law just because you’re using a camera to do it,” says Anne McCartt, senior vice president for research at IIHS. “They understand that this technology is preventing crashes in their cities.”

According to the National Highway Traffic Safety Administration, red-light running causes more than 100,000 crashes and nearly 1,000 fatalities every year, and right-angle crashes account for 46 percent of all intersection-related collisions.

“As a former police officer, I’ve seen the aftermath of some really devastating crashes,” Walden said. “Through research, we’re driven to better understand why red-light running crashes occur, and how we can suggest countermeasures that reduce the social harm that these tragic events generate.”

This Issue

Safety Is No Laughing Matter

Texas Transportation Researcher - Volume 47, Number 3 - cover

Volume 47, Number 3
September 2011
Issue Overview

On this page:

“As a former police officer, I’ve seen the aftermath of some really devastating crashes. Through research, we’re driven to better understand why red-light running crashes occur, and how we can suggest countermeasures that reduce the social harm that these tragic events generate.”
Troy Walden,
TTI Associate Research Scientist

For more information:

Troy Walden
(979) 845-9943
t-walden@ttimail.tamu.edu