Red light camera programs are a racket. A racket is a fraud scheme based on creating problems then profiting from those problems. The red light camera company uses the power of government to profit from engineers misdesigning intersections and mistiming traffic signals. The camera company gives the government a portion of the profits which gives the government incentive to maintain the racket. Together the company and government, like the old-time medicine show operator, claim their red-light cameras solve the crash problem. The company portrays the typical red-light runner as one causing a T-bone crash. It is a classic case of false advertising. The typical red-light runner is far from the portrayal. 1) According to the red-light camera violation data, the typical red-light runner enters the intersection within the blink of an eye (0.4 seconds) of the light turning from yellow to red. Government and company make 50% of its money for those blink-of-an-eye infractions, infractions which neither driver nor police officer can discern with the human eye. Let us address T-bones. How many violations end in a T-bone? Red light camera data shows 2 out of 100,000 red-light runners end in a T-bone. The camera company deliberately only shows the T-bone variety because a truthful representation is silly and the government would not buy the fraudulent nostrum 2) Had the camera been able to solve the crash problem, the red-light camera clip showing the crash would not exist. Every study on red-light cameras always proves that red-light cameras do not prevent crashes. The studies do show the cameras only transmute one kind of crash to another--a T-bone to a rear-end. And there is a scientific reason for that . . .

What problems does the government create?

Engineers are the problem, not drivers. Red light running is caused by traffic engineers misapplying math and physics which causes conflicting traffic to enter the intersection at the same time. Traffic engineers use the wrong equation to set the duration of yellow lights. The engineers plug the wrong numbers into the equation. Engineers introduce defects which are systematic, meaning that the defects exist at every intersection--it's just a matter of degree. Every driver experiences them. Every driver cannot avoid them. Eventually every driver inadvertently run red lights. Certain combinations of these engineering defects result in catastrophic collisions. Drivers cannot change the laws of physics, and so red-light running and crashes must occur.

How many violations are caused by the engineer's math mistake with the yellow?


90% of drivers running red lights run them because of this math mistake. Most of the remaining 10% run red lights due to other engineering problems--like running red lights in the middle of the night. The traffic signal is stuck red. No one is coming. Driver goes.

What percentage of red light running events end in a t-bone crash?


That is 2 in 100,000 cases of red light running end in a T-bone crash involving two vehicles going straight, and note that 90% of all crashes are caused by traffic engineers, not drivers. Yet red light camera companies pitch their product as "safety cameras" showing only those rare videos to government and public. For contrast, this video shows reality.

What percentage of red light running events are so close to the light turning red that the human eye cannot tell the driver ran a red light?


50% of those punished enter the intersection under 0.4 seconds of the light turning red. 0.4 seconds is the time it takes for human eyes to blink. Blink at the moment the light turns yellow and "ching-ching" the government takes $100.00. When you watch the video of your "violation", you cannot even tell whether anyone ran a red light. When you go to an administrative hearing, the police (if you are so lucky) recap the video. They play the video again and again. They too cannot tell that you a ran a red light. But they convict you anyway. Because if they let you go, they have to let 100,000 drivers go and there goes the money. So law enforcement holds you responsible to react and count time as well as a computer.

What percentage of red light running events occur in a fraction of a second?

70% get punished for entering the intersection under 1.0 second.

How many seconds short is the yellow light?

According to the laws of physics and measurement of human factors, about 2 seconds short for 25 mph speed limits. About 5 seconds short for 45 mph speed limits.

Do traffic engineers shorten yellow lights for the sake of the camera revenue?

No. The yellow lights are already short. Red light cameras exploit a preexisting condition.

Why are yellows short to begin with?

When traffic engineers shorten yellows, they do so to increase traffic flow or do so because their colleagues do it. The less yellow in a signal cycle, the more time drivers see green. More green means more flow. Flow is the #1 design priority for traffic engineers. #2 is safety. #8 is the ability of traffic to move legally. (TxDOT report). Shortening the yellow, regardless of motivation, also causes a radical increase in red light violations. Even a shortening of a left turn yellow from 4 to 3 seconds will increase the red light running permanently by 600%.

When a city is considering red light cameras, the city will ask the traffic engineers to review the traffic signals. In order to keep their jobs and be a team-player, traffic engineers will shorten the yellows to minimums.

What is the minimum yellow?

Traffic engineers will use ITE or MUTCD guidelines to establish the minimum. 3 seconds is the MUTCD minimum for low approach speeds of 25 mph or less. Traffic engineers think 3 seconds applies to 50 mph roads too. However these guidelines are not standards and so the engineer uses these guidelines at his own discretion, and thus risks his own legal liability. The other guideline is the ITE equation and it is that guideline that is the problem. When a traffic engineer says, "We are just using the federal guidelines", he confesses to making everyone run red lights.

What is the scope of the engineering problem?

Worldwide. The misuse of this math equation is propagated by the Institute of Transportation Engineers (ITE). ITE disseminates the misuse of the equation to traffic engineers all over the world. That is why red light cameras are all over the world. The problem began with ITE in 1965.

How many drivers are going to get tickets?

With a dozen cameras and a handful of years, a city of 100,000 will issue more tickets than its population.

Every driver who goes through a red light camera intersection regularly, will eventually get a ticket. It is not a matter choice. It is a matter of time. Approaching an intersection is identical to game of Russian roulette. The traffic engineer has always loaded the gun with a bullet or two.

Can one predict which intersections will be the most profitable?


One looks for intersections whose prevailing traffic movements conflict with the equation the traffic engineers use. If you want to open up a red light camera business, find the approaches where the most traffic must slow down before entering the intersection. Left and right turns lanes are gold mines. Intersections near cross streets and close-by business entrances are silver mines. And if you want emeralds added to your treasure, look for those intersections that have traffic signals without back plates. The glare of the Sun is a jewel. Line-of-sight problems are rubies. Nothing like a train-trestle blocking the view of the traffic signal--a particular favorite of Raleigh.

Do red light camera programs violation the US Constitution?

Yes. Americans are sensitive to issues of Constitutionality of how photo-enforcement programs operate. Photo-enforcement programs usurp the basic foundations of the US Constitution. One has to go back to basics and recall the principles. The article in the above link is written by Adam MacLeod, a law professor at Faulkner University. It is a beautiful treatise. Today's attorneys and judges are generally blind to or avoid these basic principles. They are more concerned with the letter of the law and the identification of loop holes.

Note that Constitutionality issues would not exist without the math mistakes being first made by traffic engineers. Fix the math mistakes, and the conditions which promote the other crimes disappear. The right question about legality to ask is,

Is it legal for a licensed professional engineer to make physics mistakes in his designs or specifications?


It is not legal. Every licensed professional engineer is held personally liable (not the City, not the DOT, not the company he works for) by his own State's statutes to adhere to the definition of engineering practice. The statutory definition is, "engineering practice is the application the physical and mathematical sciences." The purpose is to "safeguard the life, health and property of the public." By the misuse of the ITE equation, the engineer misapplies the physical and mathematical sciences, and puts the public in harm's way.

The only federal standard, not a mere guideline, for the yellow light duration is that traffic engineers must follow 23 CFR 655 F (MUTCD 4D.26-3). That federal regulation states, "The yellow change interval must be determined by engineering practices." The federal regulation combined with the State definition of engineering practice established the legal claim against the traffic engineer.

Who is your accuser?

The traffic engineer. And yes, there is an accuser. The traffic engineer "who signed and sealed the signal plan of record for the intersection" is accusing you of running his red light. It is the traffic engineer who set the yellow to N seconds. It is the traffic engineer who condemns you when once you see the light turn yellow, you neither can stop nor reach his intersection in under N seconds. This web site's North Carolina Exhibits present depositions of 4 traffic engineers concerning a particular intersection in Cary. Every traffic engineer acknowledges that the engineering change is forcing everyone to run red lights. But at the same time, every traffic engineer also says that all the drivers are guilty and all should be punished. Sociopathy. Also every traffic engineer claims that drivers eventually will adapt to the shortened yellow. The graphs reveal that drivers never adapt. Every traffic engineer stubbornly clings to two false beliefs: "Drivers can adapt to any length yellow light" and "Drivers will disobey long yellows." These beliefs are fictions. They both have proven false in formal studies dating as far back as 1961. Belief is irrelevant. It is physics that is relevant.

Many people like to muse that it is the red light camera that accuses you. That is wrong. What is true is this: The computer containing the red light camera and traffic signal display a guilty verdict, but the computer system has been programmed by the traffic engineer to pronounce everyone guilty. The video clip from the Star Trek episode "Court Martial" illustrates this man-vs-machine social injustice.

The government or camera company employee watching the video does judge, but his judgment is based on the misprogrammed computer.

This web site explains the math errors and omissions in detail. This web site also provides the solution.

Five Major Engineering Errors and Omissions

The Yellow Change Interval: Five Major Engineering Errors and Omissions

This paper explains the five major ways traffic engineers as a profession misapply the physical and mathematical sciences thus putting in harm’s way the life, health and property of the public.



The Solution

This paper lists the physics equations which allow different types of traffic movements to legally enter an intersection. This paper explains how the ITE change interval equation (one of those equations) can be properly used, and explains how it is misused.

Contrast between Practice and What is Required

Yellow Time: Contrast between Practice and What is Required

How much yellow time do reasonably-perceptive drivers need? Do commercial vehicle drivers need more time? This chart reveals how traffic engineers systematically short the yellow for reasonably-perceptive drivers and for various of types of vehicles.

(Click here for North Carolina specific.)

Blinded By The Truth

Does the Multibillion-Dollar Red Light Camera Sector Owe Its Existence - and Profits - to Traffic Engineers' Misapplication of the Yellow Change Interval Formula?

Traffic Technology International, a London-based journal, published this cover story about red light cameras exploiting the faulty ITE equation in its October/November 2013 issue. This story summarizes much of the literature on this web site.


Animation Slow Down at Critical Distance Animation Left Turn Slow Down at Line Animation Right Turn Animation Slow to Turn

Animations Illustrating the Problem by Johnnie Hennings, P.E., Accident Reconstruction Analysis, Inc., Raleigh.

The animations are to scale and true to the laws of physics.

In the animations you will see the "critical distance". The critical distance line marks the closest point to the intersection where the driver can still stop safely and comfortably. The line is the point of no return. By federal guideline the amount of time the light is yellow equals the time it takes the driver to traverse the critical distance on the precondition that he travels at the speed limit. You see this fact play out watching the straight-through unimpeded drivers in the following videos. But notice how the yellow will be too short for turning and impeded drivers.

  1. The first animation has the light turning yellow the moment after the left-turning driver crosses the critical distance line. The traffic engineer forces the turning driver to run a red light.

  2. The second animation has the light turning yellow the moment the left-turning driver applies his brakes in order to slow down to prepare for his turn. The traffic engineer forces the turning driver to run a red light.

  3. The third animation shows a right-turning driver. He has the same problem as the left-turning driver. The traffic engineer forces the turning driver to run a red light.

  4. The fourth animation shows a straight-through driver who has to slow down to avoid the car that emerged from a business. The traffic engineer forces the impeded driver to run a red light.

Most States implement a shorter turn lane yellows than through-movement lanes. This demonstrates that traffic engineers do not understand the kinematics of the ITE yellow change interval formula. A new federal guideline called NCHRP 731, formalizes the implementation of the error. One of the 731's authors is Richard Retting, the father of the red light camera industry in America.

I-Team:  Are Yellow Lights Too Short When Making Turns?

I-Team: Are Yellow Lights Too Short When Making Turns?

ABC WTVD, Channel 11, Raleigh, NC: May 5, 2014.

This newscast includes an interview with Dr. Alexei Maradudin, the inventor of the yellow change interval formula. Maradudin rebukes DOTs all over America for their misapplication of physics.

Kevin Lacy, a spokesman for the NCDOT, responded to ABC. Lacy claims that there is no deterministic equation which models all traffic. Lacy is wrong. The deterministic equation not only models all traffic, but all objects in the universe. It is a = v/t, eq. 41 here, of Newton's second law of motion. The equation for turning traffic is eq. 13 here. The red light camera empirical data proves that the deterministic equation is the solution. That should be expected. Everyone (other than traffic engineers) have known about this equation since 1687 when Isaac Newton discovered it.

Johnnie Hennings, P.E., an accident reconstructionist, wrote a rebuttal to Kevin Lacy's/NCDOT's letter.

Derivation of the ITE Yellow Change Interval Formula

Derivation of the ITE Yellow Change Interval Formula

This paper shows the mathematical steps it takes to derive the yellow change interval formula from scratch; that is from F= ma--Newton's second law of motion. The paper describes the physics and the assumptions.

Misapplied Physics Profits Red Light Camera Companies

Misapplied Physics in the International Standards that Set Yellow Light Durations Forces Drivers to Run Red Lights

This paper describes the formula, what it does and how today's traffic engineers misapply it. This paper also presents red light camera citation data showing how minor changes in yellow light durations dramatically and permanently affect red light running counts.

Maradudin's Letter to ITE Condemning ITE for Misapplying His Formula

Maradudin's Letter Condemning ITE for Misapplying His Formula

This is a letter (July 2015) from Professor Alexei Maradudin, the last surviving inventor of the yellow change interval formula. In an upcoming yellow light guideline which ITE is about to publish (called the RP), ITE misquotes Maradudin. Maradudin does not take kindly to that. Maradudin does not like ITE misapplying his formula to turning motions and to any motions impeded within the critical distance. Maradudin does not like that ITE intentionally and knowingly forces drivers to run red lights by establishing a standard which sets the speed used in the formula to values less than the posted speed limit.

Yellow Change Interval Dos and Donts

Dos and Don'ts of the Yellow Change Interval Formula

This is a letter (July 2013) from Professor Alexei Maradudin, the last surviving inventor of the ITE yellow change interval formula. Every Department of Transportation in the world does the don'ts which cause drivers to inadvertently run red lights.

The Problem of the Amber Signal Light in Traffic Flow

The Problem of the Amber Signal Light in Traffic Flow

Gazis, Herman and Maradudin (GHM) co-authored this paper in 1959. In 1965 ITE miscopied this paper's equation 9 into its Traffic Engineering Handbook. By omitting GHM's "Analytical Considerations", ITE has been instructing traffic engineers to abuse this formula for over 50 years.

The Problem of the Amber Signal Light in Traffic Flow

Determination of Left-Turn Yellow Change and Red Clearance Interval

The American Society of Civil Engineers (ASCE) Journal of Transportation Engineering published Dr. Chiu Liu's paper in 2002. This paper is the follow-up work to Gazis, Herman and Maradudin. Dr. Chiu Liu's formula computes the minimum yellow duration which allows all traffic to move legally. Chiu's formula is equation 13 on page 454.

This paper is peer-reviewed.

The beginning of the paper states explicitly that the turn lane yellows must be longer than the straight-through.

Uncertainty in the Yellow Change Interval

Uncertainty in the Yellow Change Interval

When seeing the light turn yellow, do you stop or do you go? Many times the decision is not clear. Can the indecision be expressed mathematically? Yes. This paper computes the uncertainty in the yellow change interval. Should not law enforcement be aware of this uncertainty? Should not law enforcement grant the driver the tolerance required by the engineering?


Television Newscasts

Science Proves Yellow Lights too Short

I-Team: Are Yellow Lights Too Short When Making Turns?

ABC WTVD, Channel 11, Raleigh, NC: May 5, 2014.

Science Proves Yellow Lights too Short

I-Team: Raleigh Fraudulently Issuing Red Light Camera Tickets

ABC WTVD, Channel 11, Raleigh, NC: Feb 5, 2014.

Science Proves Yellow Lights too Short

Red light Camera Traps: Does Science Prove Our Yellow Lights are too Short?

"The Institute of Traffic Engineers miscopied the yellow change interval formula into its 1965 engineering handbook. Traffic engineers, the so-called experts, do not know the math and science behind their own formulas."

CBS WTKR, Channel 3, Hampton Roads, VA: February 5, 2014.

WTKR. Newport News Re-evaluates Yellow Times

Newport News Re-evaluating Yellow Light Times after NewsChannel 3 Investigation

CBS WTKR, Channel 3, Hampton Roads, VA: February 7, 2014.

WTKR - Redflex has Violation Calculator

Redflex Tells Local Cities Where to Put Cameras Based on ‘Violation Calculator’

CBS WTKR, Channel 3, Hampton Roads, VA: February 19, 2014.

WTKR proves what we suspected. Redflex knows physics too. Given the predictable failings of the ITE yellow change interval formula, Redflex wrote a violation calculator to compute exactly where the engineering failures produce the most revenue.


Preexisting Condition - Yellows Too Short

Many people assume that cities have a nefarious agenda which calls for the shortening of yellow lights once the cameras go in. That assumption is false. Cities need not shorten yellow lights in order for a handful of cameras to flash tens of thousands of innocent motorists annually. The "federal guidelines" already makes yellows too short. When you hear a city or a DOT justify its yellow times saying, "We are just following federal guidelines", they are truly saying, "We are ripping you off and causing many of you to crash."

The federal guidelines consist of two things. 1) A math formula called the ITE yellow change interval formula, and 2) The MUTCD which sets the minimum and maximum lengths of a yellow light.

Both guidelines are wrong. Adherence to these guidelines force hundreds of millions of drivers who are doing nothing wrong to unintentionally run red lights daily.

It gets much worse than this. There are cities like Winnipeg, Chicago and New York City who pride themselves with not complying to the ITE formula. They set their yellows even shorter than the formula's calculation. But the ITE formula does apply physics. The ITE formula satisfies one type of traffic movement which represents the shortest possible yellow time. Any shorter than the ITE calculation grows a steady stream of unintentional red light runners to a fast-flowing river.

The Red Light Cameras of Cary, North Carolina

by Chad Vader


This is a true story. This is an account of the red light camera program that existed in the Town of Cary, North Carolina. Dr. Moley represents the real-life person Brad Hudson. Hudson came to work once a month and without looking at the videos, accused and convicted everyone of running a red light. Baby Cookieflex plays the part of Maria, an employee of Redflex. She worked at the Safelight office in Cary. If you had a problem with the ticket, the Cary police sent you to Maria or to Frank Rubino. Maria indeed said, "Aren't you happy that your $50 goes to public schools? Don't you care about children?" Until the very end of the Safelight program, Cary had spread Redflex's propaganda line to the local TV stations and the newspapers. Cary never said what percentage goes to schools. By contract, the Town of Cary paid Redflex $49.50 of every $50 for approaches which had less than 120 violations per month. That is 99%. That leaves 50 cents to the schools. The contract contained a tiered compensation clause. When the Town of Cary and the NCDOT engineers caused more than 120 drivers to run red lights per months for an approach, Cary had to pay Redflex 60%. Once Cary took out its own administrative costs, about $5.00 out of $50.00 went to the schools.