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A yellow light is supposed to mean prepare to stop, but for many drivers yellow is the new green.Brett Hillyard/Getty Images/iStockphoto

On Feb. 3, 1965, members of the Sebewaing Woman’s Club met at the home of Mrs. John Konkle in that small Michigan town to hear about the life of William L. Potts, an influential inventor known as “Mr. Traffic Light.”

According to a report in the Sebewaing Blade and Unionville Crescent, Potts’s daughter told the club that her father was born on a Michigan farm in 1882 and went on to become a Detroit police detective. He spent most of his life in that city, serving 26 years on the force and 15 years in the safety and traffic department of the Detroit Automobile Club.

It was while working on the police force in the 1920s, Potts’s daughter said, that her father designed and built the first automatic three-lens traffic light. At that time, only the red and green signals introduced in 1914 were used to direct North American automobile traffic. Potts’s prototype cost $47 to construct and featured three lights: red, yellow and green. The yellow light signalled drivers to slow down and prepare to stop. Potts’s invention, which became the world’s first three-lens automatic traffic light, was installed in 1921 in downtown Detroit. Potts – the father of the yellow traffic signal – retired in 1954 and passed away in 1956.

It is perhaps a good thing that Mr. Traffic Light is not currently around to see how poorly modern drivers treat his invention.

Potts created the yellow to caution drivers and allow them to yield. It’s the law in every province. According to the Ontario Highway and Traffic Act, “A yellow – or amber – light means the red light is about to appear. You must stop if you can do so safely; otherwise, go with caution.”

It’s the ability of drivers to surmise if they can stop “safely” that causes the problem, along with their interpretation of the words “go with caution.”

Today, 101 years after the installation of the first modern, three-lens traffic light, yellow is the new green.

Red is the new yellow. Green is the new red. It’s all very mystifying.

A yellow light is supposed to let drivers know the light will soon be red and that they need to prepare to stop. Many do not do this. They appear to believe that the yellow light means you may turn left, go straight or turn right after yielding to vehicles and pedestrians already in the intersection (minus the “yielding to vehicles and pedestrians” part).

As a result, three kinds of drivers can be found at the average North American set of traffic lights.

  1. Drivers stopped at the red light.
  2. “Left-turners” on the yellow light trying to make left turns.
  3. “Blow-throughers” on the yellow light travelling straight through the intersection.

Left-turners drift out into the intersection and wait for an opportunity to turn. Meanwhile, the blow-throughers coming the opposite direction travelling straight through the intersection treat the yellow light as a “hurry up” signal and speed through before it turns red. It’s not just one blow-througher running the yellow, it’s often three or four, with the last two generally blowing through the red.

This leaves the left-turner stranded in the intersection until the lights have changed to a solid deep red. Then they make their turns.

Finally, the drivers who have been waiting at the red have watched half the time on their green lights evaporate, and so the left-turner and blow-througher cycle repeats itself.

I’m going to guess thirty minutes after Mr. Traffic Light put up his first set, some guy blew through a yellow light. Human misbehaviour is hardly a new phenomenon. What we are seeing on our roads, however, is a daily abuse of the most basic driving principles. Sure, we can debate the benefits of traffic lights versus roundabouts (roundabouts are better), but that doesn’t excuse the horrible treatment people are giving poor Mr. Potts’s wonderful invention.

He deserves better treatment. In 1913, 4,000 Americans were killed in car crashes. The carnage started early. Potts created a device that has no doubt saved countless lives and he didn’t do it to get rich. William Potts never made a cent from his three-lens automatic traffic light; as a city worker he could not patent his invention. Give him the respect he deserves, for goodness sake. Stop when you see that yellow light or go forward with great caution.