Math + Physics + Fancy Language + Sneeze = Beating Traffic Ticket

Apr 16, 2012
Originally published on April 16, 2012 6:12 pm

Stories about someone beating a traffic ticket by using an imaginative defense always seem to strike a chord.

That probably explains why this tale from California has slowly gained attention over the past week. As Physics Central explains, Dmitri Krioukov, a physicist based at the University of California, San Diego, used some math, some physics, some scientific language and the claim of a critically timed sneeze to help persuade a judge to drop a ticket he'd gotten for allegedly running a stop sign.

We've read through pieces done by Wired, Yahoo and others, as well as the four-page paper, called Proof of Innocence, that Krioukov produced to make his case. We come away with this conclusion:

Basically, he convinced the judge that the police officer's view was obscured at the critical moment. At the instant his vehicle stopped, Krioukov argued, another car passed between him and the officer. So the officer didn't see Krioukov's vehicle come to a halt.

The physics and math came in when Krioukov showed with graphics and formulas that the officer might have come to a mistaken conclusion because:

"It is widely known that an observer measuring the speed of an object passing by, measures not its actual linear velocity [but] the angular one. For example ... watching a train approaching us from far away at a constant speed, we first perceive the train not moving at all, when it is really far, but when the train comes closer, it appears to us moving faster and faster, and when it actually passes us, its visual speed is maximized."

But the train, he argued, might never have changed its speed.

The officer, Krioukov maintained, assumed that the car went through the intersection because it appeared to be gaining speed as it approached — though he insists it was not.

And that's where the sneeze comes in.

Krioukov says in his paper (the "he" is a reference to himself) that:

"In fact, he was sneezing while approaching the stop sign. As a result he involuntary pushed the brakes very hard. Therefore we can assume that the deceleration was close to maximum possible for a car."

In other words, he stopped quickly because he sneezed as he hit the brakes. All this supposedly happened just as the other car blocked the officer's view.

The court apparently bought his argument.

"The judge was convinced, and the officer was convinced as well," Krioukov told Physics Central.

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The study of physics has helped to explain some of life's greatest mysteries: the laws of motion, the equivalence of energy and matter.

UNIDENTIFIED MAN: E is equal to MC squared and it's energy is equal to mass.

CORNISH: And now, how to get out of a $400 traffic ticket. Dmitri Krioukov, a research scientist at the University of California San Diego, was cited for failing to make a complete stop at a stop sign. But NBC San Diego reports that rather than pay up, the 42-year-old physicist challenged the ticket by taking a page from the book of Jerry Seinfeld.


JERRY SEINFELD: (as Jerry) Unfortunately, the immutable laws of physics contradict the whole premise of your account.

CORNISH: That's right. In a four page paper to the judge, Dmitri Krioukov explained that his ticket defied the laws of physics. He wrote that, quote, "the police officer made a mistake, confusing the real space time trajectory of the car, which moved at approximately constant linear deceleration, came to a complete stop at the stop sign and then started moving again with the same acceleration for a trajectory of a hypothetical object moving at an approximately constant linear speed without stopping at the stop sign." Did you get all that? Neither did we.

Krioukov added that the officer's car was briefly obstructed by another vehicle at the time he approached the stop sign and, ultimately, the judge was convinced. No ticket, no traffic school. Dmitri Krioukov fought the law and the law of physics won.


THE CLASH: (Singing) Breaking rocks in the hot sun. I fought the law and the law won. I fought the law and the law won. I needed money 'cause I had none. I fought the law and the law won. I fought the law and the law won. Transcript provided by NPR, Copyright NPR.