Since the city increased the length of the yellow light at Oak Street and Carroll Boulevard last year, there have been fewer vehicle crashes and fewer violations recorded by the red-light cameras.
A recent report to Denton City Council showed a 60 percent drop in red-light camera violations between April and December. In addition, accident data released to the Denton Record-Chronicle recorded just four collisions after the light change, a significant drop in the rate of crashes compared to the 26 months before.
Last year, council member Keely Briggs asked whether the city could test adding one second to all the yellow lights at one intersection. Nationwide, some advocates have argued that such timing changes could do more to improve compliance than the cameras. Briggs said she wanted to know whether Denton motorists would better obey the lights or would adjust to the longer yellow and continue to race the stoplight.
“I was trying to figure out a way to get a bit more data,” Briggs said. “By having the pilot program in place, where we see the data, we’ve reduced the violations by more than half.”
She’s opposed to the red-light camera program, but she didn’t want to remove the cameras if they really were making Denton’s troublesome intersections safer, she said.
The city’s traffic engineers agreed to test the lights at Oak and Carroll, even though they had just realigned the timing as part of a North Central Texas Council of Governments program to improve traffic flow — and to help the region’s air quality by reducing idling at intersections.
Staff in the engineering department said they don’t yet know whether the yellow-light timing change has created additional congestion in the area, according to city spokeswoman Jessica Rogers.
However, about eight months of camera data show a consistent drop in violations, both month-to-month and overall.
For example, April and September had the most red-light camera violations in 2017. In April and September 2018, the violations dipped 62 percent and 58 percent, respectively.
Total red-light violations approached the single digits in November (eight) and December (10), suggesting that motorists aren’t adapting to the change to race the stoplight.
Accident counts also appear to have improved. Denton police responded to 21 collisions in the 26 months before the timing change, and just four in the eight months following.
Oregon resident Mats Jarlstrom has become known nationwide for his efforts to highlight the problem with the timing of yellow lights, particularly for cars turning into an intersection.
After his wife got a ticket in Beaverton, Oregon, the audio engineer challenged that city’s red-light camera program using some of the same algebra used in kinematics, a branch of mechanics.
“What it boils down to is the mathematics motion of objects,” Jarlstrom said. “NASA scientists understand it.”
He notes that traffic engineers still use the same calculations for yellow lights established by a trio of General Motors engineers in 1959. He is skeptical that the standards won’t need to be revisited before the widespread adoption of autonomous vehicles.
But so far, the Federal Highway Administration defers signal timing to the Institute of Transportation Engineers, and while the ITE has included Jarlstrom in recent conferences, it has not recommended any changes to the standards.
Briggs noted that opposition to the city’s red-light camera program crosses political party lines, but the city would face a heavy penalty if it exits its contract early.
Denton’s camera program came under fire last year after a Denton Record-Chronicle investigation uncovered that, for a brief time, the program wasn’t paying for itself when it came to reviewing video of violations. In addition, a former assistant police chief accrued $122,000 in overtime pay over a three-year period reviewing video of violations.
Denton’s current contract with Redflex expires on July 20. Crews installed the first cameras in Denton in 2006, the year after the city entered into its first contract with Redflex Traffic Systems, part of Australia-based Redflex Holdings.
The first contract covered four intersections. The city renewed the contract and added two more intersections in 2011. In 2014, the program grew to cover 11 intersections in all, including freeway interchanges.
The cameras run 24 hours per day, taking photographs and a short video of vehicles that run red lights. Violators get issued a civil citation that comes with a $75 fine.
The enforcement program has become increasingly controversial, with the Texas Legislature flirting with prohibiting red-light cameras and individual motorists challenging the fairness of their tickets in court. Unpaid tickets cannot be reported to credit bureaus, nor can a city arrest someone for an unpaid ticket.
Both supporters and critics say the cameras affect safety at covered intersections. Supporters say the cameras help reduce collisions in the intersection while opponents say they can increase rear-end collisions because motorists slam on the brakes. Critics also say the tickets disregard due process because the moving violation is not observed in person by a police officer.
So far, the council has not discussed whether to renew the contract nor has such a discussion been placed on the matrix of future agenda items. With the council’s current membership, there may not be enough council members who support continuing the program.
Most of the money collected from red-light camera tickets doesn’t go into city coffers. About one-third goes to Redflex to support the cameras. Another third goes to the state of Texas for trauma centers. The remaining third stays in Denton, with most of it underwriting the program’s administration. Only about 10 percent of the total amount collected each year from Denton motorists helps pay for traffic safety improvements in the city, according to city financial reports.
But this week, the city staff recommended another intersection as a good candidate for a yellow light timing extension beginning March 1: the northbound and southbound cameras at Interstate 35E and Fort Worth Drive.