I am a licensed professional engineer. My expertise is in the field of photo enforcement technology, and the physics of traffic movement and traffic signal timing. I have examined photo enforcement technology across the country, including red light cameras, speed cameras and bus stop-arm cameras. My findings and conclusions are within a reasonable degree of engineering certainty.
In Suffolk County, NY, pursuant to a red light photo enforcement contract with Affiliated Computer Solutions (ACS), and thereafter amended to Xerox Local and State Solutions and Conduent, red light cameras were installed throughout Suffolk County beginning in 2010.
My investigation reveals that the red light camera installations throughout Suffolk County were implemented pursuant to engineering plans that were not sealed or signed by a NY professional engineer. Also not signed and sealed were computations of yellow light durations and intersection traffic signal plans. All are explicit violations of NYS law.
“As traffic signal and red-light camera installations involve traffic, structural, electrical and other types of engineering, this work would fall under Education Law, Article 145, section 7201 – Definition of practice of engineering.”
“Section 7209 of the State Education Law requires every professional engineer have a seal and identifies when it must be applied.”
Jane W. Blair PE, Executive Secretary
NY State Board for Engineering, Land Surveying and Geology
Red-light camera programs promote changing driver behavior and improving roadway safety. However, after a couple of years of running a red light camera program, the outcome is not as advertised. Hidden from the public is the proof that red-light camera programs offer no net reduction in crash rates:
The 2021 Suffolk County Red Light Camera Safety Program Analysis Report:
- The overall number of collisions has increased by 15.1%,
- The right-angle collisions have decreased by 8.3%,
- The rear end collisions have increased by 54.9%, and
- The collisions involving injury have decreased by 10.3%.
There is a scientific reason why red-light cameras are ineffective in reducing crashes. The scientific hypothesis behind using red-light cameras is that reckless driving is responsible for red-light running. However, the data shows that there is no significant reduction in red-light running. After red-light camera ticketing, science concludes that drivers are not the cause and that there must be some other mechanism causing red-light running and crashes.
Science reveals that faulty engineering is the cause. There are specific easily-identifiable problems with a math equation traffic engineers use to determine the duration of the yellow light. The math equation comes from the Institute of Transportation Engineers (ITE). This math, by opposing the laws of physics, causes over 90% of red-light running, which red light camera companies exploit.
The presence of the red-light camera often exacerbates the problem with ITE’s math, making outcomes worse. Crash rates often significantly increase (even to 1000%) in that specific intersections as shown in this 2016 Suffolk County Red-Light Camera Safety Program Accident Analysis report:
The other 90+ intersections in Suffolk County, NY show less dramatic increases and decreases.
Without going deep into the math, here is the ITE yellow change interval practice. Introductory physics students should spot a couple of the errors immediately:
Y is the yellow light duration, tp is the perception-reaction time for 50th percentile of sedan drivers seeing a light turn yellow, “a” is the comfortable stopping deceleration for the 50th percentile of sedan drivers and v is the initial velocity drivers approach the intersection. G is the grade of the road (0 = level road). g is earth’s gravitational acceleration.
The equation should be:
tp and “a” should accommodate all allowed on the road, and vc is the speed of the vehicle at the comfortable-stopping distance upstream from the intersection. Ignore Γ (Greek letter gamma) for now. Γ = 0 when the grade of the road is level.
The Suffolk County Red-Light Camera Safety Program Accident Analysis Reports illustrates that Suffolk County, NY issued more tickets than its population, well over 1.5 million (U.S. Census). Suffolk County enforces an ordinance that requires drivers to change Isaac Newton’s second law of motion, F= ma, which describes the relationships between distance, time, velocity and acceleration in this universe. This is how red light camera corporations and governments generate revenue. It is an insidious way to tax and generate money from the public.
Fixing the math is simple; however, fixing the math makes the joint-venture red-light camera programs unprofitable. Further, traffic engineers do not want to fix the math because this would expose their liability which is billions of dollars in property damages, injuries and death. These math errors have been in place since 1965. American photo enforcement technology, beginning in the 1990s in New York City, has been capitalizing on them.
Tragically, municipalities who fall for and adopt the red light camera scheme eventually realize and become complicit in its injustice to its citizens. The municipalities who adopt these programs and those who help set up and administer them, are all complicit in the knowledge that they endanger lives and are involved in blatant profiteering. The traffic engineering community is aware of the math mistakes in traffic signal timing and photo enforcement technology. The Institute of Transportation Engineers (ITE) admitted in March 2020 that its practice is filled with math errors that cause drivers to run red lights.
Brian Ceccarelli, PE
