Red Light, Green Light

Some cities may have second thoughts about timing traffic lights so drivers can hit greens. Why would cities prefer a stoplight instead of a “go” light?

You know the term conspiracy theory? It’s a way of explaining an occurrence as part of a plot by some group or alliance, rather than recognizing it as an isolated or random event. One reason we’re familiar with the term is that we often use it dismissively to characterize explanations that seem too far-fetched to be believable.

Two wacky conspiracy theories we’ve all probably heard are that NASA faked the Apollo moon landings and that the U.S. government orchestrated the 9/11 terrorist attacks. So to call someone a conspiracy theorist is just a polite way of saying that he or she is part of the lunatic fringe.

Conspiracy theory is the term that came to mind when we first heard an explanation of the traffic jams in major British cities caused by the timing of red lights. We first saw the claim on a blog called “Wallet Pop,” in an entry titled, “Waiting at too many red lights? The taxman likes it that way.”

The blog writer began by describing something called the “green wave,” which is a...