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Wilmington, NC; Ch 2: Engineer Caught Lying

Updated: Nov 21, 2023

When confronted about the shortness of a yellow traffic light, traffic engineers lie. If they tell the whole truth, the liability consequences are severe, even unto hundreds of millions of dollars of civil and criminal penalties. And so they lie to protect their careers, their colleagues and their employers. They lie to conceal their incompentence--an incompetence which has saturated the traffic engineering profession since 1965. An attorney needs to know what the traffic engineer is doing wrong and how the traffic engineer defends himself. This article is the necessary primer.

This article contains the details of a confrontation between a red-light camera ticket recipient and a traffic engineer. The confrontation occurred on September 22, 2023. The engineer timed the yellow light at the intersection where the accused got his ticket. The intersection is Market St at N. 23rd St in Wilmington, NC. The yellow light duration is too short even by NCDOT standards, let alone by first principles of physics. Had the traffic engineer calculated the yellow even by NCDOT standards, the accused would never have received a ticket.

Below I enumerate the traffic engineer's responses to the accused's questions. The engineer's responses are typical. The engineer claims to have followed the NCDOT standards. The engineer then sets out to intimidate the accused with technobabble. The engineer hopes the accused will just go away. But the accused, who is a private-sector electrical engineer, knows more about engineering than the traffic engineer. The accused has done his research. The accused knows that many engineering calculations are wrong, but the accused has not yet learned to refute the babble of a traffic engineer. It takes years for a person to speak the pseudo-science language of the traffic engineer. I, instead, proffer the refutation to each of the engineer's claims. For professional engineers licensed in the state of North Carolina, lying and incompetence are unlawful under the Professional Code of Conduct: NCAC 21-56.0701.


The following is the North Carolina Rules of Professional Conduct.

Rules-of-Professional-Conduct-21-NCAC-56 .0701
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Paragraph (b) requires the engineer to protect the public. Paragraph (c)(1) requires the engineer to be competent. Paragraph (d) requires the engineer to be objective and tell the truth.


The following is the response of the NCDOT traffic engineer to the accused. The engineer responded in red. Compare the responses to the facts in the table below.

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NCDOT Traffic Engineer's Responses


A speed study showing the 85th percentile is required to use a design speed that is different than the posted speed limit.

Incompetence and Lie

The engineer incorrectly thinks that the speed study mentioned under the "Notes" section in Std. 5.2.2 changes the design speed of the road. The speed study mentioned under the "Notes" section in Std. 5.2.2 is to calculate an "approach speed". The approach speed is independent from design speed. The approach speed is only to used to change the value for "v" in the yellow light equation. It is common knowledge among engineers to use "approach speed", not design speed and not the posted speed limit, for "v" in the equation. It would be negligence if the engineer did not know this. Therefore, it is probably a lie.


The NCDOT encourages drivers to follow the posted speed limit.


While he says that to the accused, like all traffic engineers, he really believes that posted speed limits are "suggestions." Posted speed limits most often contradict the engineer's design speed. Engineers hate that. Posted speed limits are established by city councils and legisators who know nothing about what speed is safe. City ordinances arbitrarily and capricously round down the engineer's design speeds to numbers printable on speed limit signs. An engineer would prefer seeing speed limits of 21 mph, 34 mph and 42 mph. But city ordinances round down the speeds to 15 mph, 25 mph and 35 mph respectively. This rounding-down makes speed traps -- as well as yellow light traps which is the problem the accused is arguing. A "design speed" is the natural, most comfortable and safest speed to travel. Posting a speed limit lower than the design speed increases crashes. Increases! Not decreases. For illustration, what affect would a 25 mph speed limit sign have on the interstate? To bridge the gap between the posted speed limits and design/approach speed, the federal guidelines instruct traffic engineers to set "v" to the posted speed limit + 7 mph as the default. All traffic engineers know the "+ 7 mph" rule, yet they maliciously conceal this fact from the public.


At the time of the speed study, there was no determination made to change the design speed at this location.

Lie Incomptence

Again, repeating item 1, the speed study talked about in the Std 5.2.2 is not for changing the design speed. A speed study was done was done at this intersection. The speed was calculated to be 44 mph. The posted speed limit is 35 mph. This gap shorts the yellow light by 0.7 seconds. The accused ran the light by 0.3 seconds. Had the engineer understood his own spec, the accused would not have gotten a ticket


ITE's recommended practice for determining change and clearance intervals suggests using 1.0 as the perception-reaction time. NCDOT exceeds this recommendation by using 1.5 seconds.

Not the whole truth Incompetence

ITE suggests 1 second. That part is true. But ITE admits that 1 second works only for drivers with slower reaction times than the 50th percentile sedan driver driving on dry pavement. Consider what that means! This means that even on a good day, ITE recommends that traffic engineers force half the driving population to run red lights. Such is the outcome of designing for the "50th" percentile driver. To completely undo NCDOT's claim of generosity, there is another variable which one inputs into the equation: comfortable stopping deceleration. Deceleration also affects the yellow light duration. For deceleration, ITE recommends 10 ft/s/s; the NCDOT uses 11.2 ft/s/s. 11.2 shortens the yellow light. In the end, it is a wash. ITE and the NCDOT use roughly the same times. One should note that 1.5 seconds and 11.2 ft/s/s are AASHTO's values for perception-reaction time and deceleration. AASHTO's values are for emergency stopping, as if a cow wandered out onto the road. There is a bigger error here. The argument over using 1.0 vs 1.5 secs, 10 vs 11.2 ft/s/s, is moot. Any use of such constants are unlawful. Using a percentile to describe all traffic approaching an intersection is a mathematical oxymoron. A percentile always excludes a subset of the driving population. In the science of mathematics, using percentiles and applying them to the entire population is called misapplications of stochastic methods. The misapplication of the mathematical sciences is unlawful under NCGS 89C-3(6).


NCDOT does not operate red light cameras.


Attorneys beware. This response is more than just Pontius Pilate washing his hands. The engineer is telling the attorney that neither his employer the DOT, nor he himself as its employee, can be held liable for a red-light camera ticket. Every facet of the engineer's response is a lie. 1. A licensed professional engineer is personally liable for all his engineering works. It does not matter who is employer is. He is liable always. His employer may be liable too. With regards to engineering works, the licensed PE has authority over his employer. A licensed PE can never say, "The devil made me do it." Suing a professional engineer for engineering malpractical is legally identical to suing a doctor for medical malpractice. Both are licensed professions. 2. The DOT operate the most critical part of the red-light camera system. The DOT provides the red-light camera firm access to the DOT's vehicle registration database. Without providing that access, the red-light camera firm could not make money. As partner to the red-light camera firm, the DOT marries license plate numbers to vehicle owners and addresses. Given the names and addresses, the red-light camera firm mail tickets to vehicle owners. 3. Though the state attorney general argues that the NCDOT has soverign immunity and thus is not liable from such civil suits, the argument is false. Under tort law, the NCDOT forfeits itself sovereign immunity when it partners with a private company. The NCDOT partners with the private red-light camera firms Verra Mobility and Conduent. It is data for money exchange.


Overarching Errors

There are larger engineering malpractice than the ones the traffic engineer addresses.

Though I didn't mention it, the accused requested a crash study for this intersection. The NCDOT gave him one. The NCDOT performed a before-and-after red-light camera crash study for his intersection. The study revealed the red-light camera inceased the crash rate. When enforcement worsens things, then it is an engineering problem. The engineer is now violating the prime directive of the engineer practice statute: to safeguard the public's life and health. By not looking into this, the engineer is negligent.

In the confrontation, the accused used NCDOT Std. 5.2.2, Sheet 5 of 5, Determination of the Yellow Change and Red Clearance Intervals for his defense. The traffic engineer recognizes Std. 5.2.2 as authoritative yet incorrectly assumes that NCDOT Std. 5.2.2. qualifies as an engineering practice under law. An engineering practice, by statutory definition NCGS 89C-3(6), is a practice which correctly applies the mathematical and physical sciences. However, the yellow change interval equation and the numbers traffic engineers plug into it are mathematically incorrect. Therefore, Std. 5.2.2 is not an engineering practice. Instead of using physics as the authority to use the equation, the traffic engineer uses the Institute of Transportation Engineers (ITE) as the authority. ITE has the same authority as WalMart. As a matter of interest, ITE explicitly disclaims the accuracy of any of its publications.


As an attorney, you need to be confident in your knowledge that traffic engineers cause over 90% of red-light running and crashing. Calculating a yellow change interval in contradiction to what physics requires of time and distance for vehicles approaching a traffic light, makes us cross the stop bar just after the light turns red. In some cases like turning, the yellow is so short that it places us inside the intersection several seconds after the light turned red when conflicting traffic gets the right-of-way. Believe it or not, there is an easy solution to the whole problem. But the hubris of traffic engineers wills them to lie and protect themselves rather than admit that the "2" in the yellow light equation should not be there. What traffic engineers have been doing to the public for over 50 years is worse than what lead in pipes, asbestos in buildings and PCBs in ground water has done to life. Remove the "2" and the whole red-light camera industry disappears, and there will 90% fewer red-light runnners and crashes. The relationship between time, velocity and accleration is t = v/a. Not t = v/2a. The yellow light is half the time it takes to stop. That is the problem. While t = v/2a works for one special case of traffic movements--traffic going straight without slowing down, it fails for all the rest.


The next post shows an email thread where state and city traffic engineers knew they made a serious mistake, but even when the accused pointed out the mistake, the engineers conspired and lied about the mistake.

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