The Laws of Physics Trump Traffic Laws

New submitter HeLLFiRe1151 sends this quote from Physics Central: "Here's a practical application for your physics education: using math to successfully beat a traffic ticket in court. Dmitri Krioukov, a physicist based at the University of California San Diego, did just that to avoid paying a fee for (purportedly) running a stop sign. Krioukov not only proved his innocence, but he also posted a paper detailing his argument online (PDF) on the arXiv server."

Comments

Partially Blocked View

[WrongSizeGlass]

When another car partially blocked the officer's view of Krioukov's car momentarily, the officer could have missed the brief yet crucial timing of his stop. At least, that's Krioukov's version of the case.

Physics explained what the officer saw (or thought he saw) but another car explains what the officer didn't see (Krioukov stopping at the stop sign).

Re:Partially Blocked View

[Anonymous Coward]

I can tell you as a career prosecutor that usually if you want to challenge something in court you need to make sure you imediately ask the court for a jury trial. Otherwise you won't get common citizens to try your case, but just a Judge who has a working relationship with the officers all the time. Experience shows that if a case is tried to a Judge you are most likely to be found guilty. Sadly I once had a Judge say at the end of a morning in court, "If I think they are not guilty, I give them a lower fine." Juries are always willing to let you off if you can give them any excuse to do so.

Re:Partially Blocked View

[TapeCutter]

he is doing some pretty wreckless sciencing too!

Not guilty your honour; Albert's famous 1905 paper was 3 pages long with no references.

Re:Partially Blocked View

[maxwell demon]

More importantly, it contains a false claim: It claims it proves innocence, while in reality it only disproved the evidence of guilt: It does not prove that he actually stopped, it only proved that the officer cannot know whether he did.

Re:Partially Blocked View

[Anonymous Coward]

I tried to use math to defend myself recently when ticketed for using a cel phone in a school zone. As an aside, I was using it legally (hands free) and picked it up after I exited the school zone, the officer said, "you picked it up about 5 feet before the end of the zone."

It was a very, very interesting experience and I pretty much learned the point you just made AC. At the end of the day, in which I defended myself with math/physics the judge said, "I feel like I just had a college physics class. You know, there are two school zones on that street. You may have been in the zone, you may not have. I don't care, you have no business being on your phone on that street. You are free to appeal my decision.

The fine was an annoyance (like 150) but I found it a very interesting experience in how small suburbs within cities make money and how a person going in there to defend themselves has basically no chance.

IAAL, and what you did is a common mistake made by many clever self-represented litigants. In order for the judge to properly assess the mathematical argument you wanted to use in your defence, you would have needed to introduce independent expert evidence by (probably) an engineering firm that specializes in motor vehicles and accident reconstruction. You, as a party to the proceedings, cannot be your own expert. This type of evidence would cost at minimum a couple of thousand dollars, and would need to be disclosed within the timelines according to your jurisdiction's laws and court rules, and in most cases the other side would have a chance to bring their own expert in to rebut yours.

Without expert evidence, a judge cannot weigh the validity of your math argument, because judges are not supposed to be experts on math. They are, however, experts on law and testimonial evidence. In your case, leaving aside the math, you admitted to using your cell phone on a street with a school zone, so that is not in dispute. A police officer gave his eyewitness testimony that you picked up your phone in the school zone; your evidence is that you didn't. Classic he-said/she-said; if the judge has no other evidence to believe that the police officer may be lying, and no independent expert evidence that the officer was mistaken, and undisputed evidence that you used the phone somewhere on the street in proximity to the school zone, then the judge must accept the officer's evidence and find you guilty.

If you wanted to raise reasonable doubt, you could have spent 10x to 100x more than the cost of the fine, and procured expert evidence about your car velocity, your cell phone records, etc. but it would not have been worth it to you. BTW, the physicist in the original article didn't win because of his math; he won because the police officer admitted that another car obscured his vision when the physicist might have stopped at the sign, and that would be enough for reasonable doubt.

April Fools

[Anonymous Coward]

The article was posted on April 1. (Need I say any more?) See the discussion on the PhysicsBuzz blog for details.

http://physicsbuzz.physicscentral.com/2012/04/physicist-uses-math-to-beat-traffic.html

This is an April Fool joke

[1u3hr]

http://arxiv.org/abs/1204.0162

The Proof of Innocence
Dmitri Krioukov
(Submitted on 1 Apr 2012)
  A way to fight your traffic tickets. The paper was awarded a special prize of $400 that the author did not have to pay to the state of California.

If you think this really happened, find a citation for the case that doesn't end up back at this same article.

Actually..

[wanax]

It turns out that humans are really poor at estimating velocity unless they conform to Newtonian accelerations very closely.. While there has been a lot of research on these issues, I'd like to refer to one of my favorite papers, Sverker Runeson's 1975 paper "Constant velocity — Not perceived as such".

http://www.springerlink.com/content/nt61hh074k7123q5/

Tried it.

[tverbeek]

I once used physics to argue that a speeding ticket I received was bogus. I explained that even if I was traveling at the speed the officer claimed (unlikely in the underpowered subcompact I was driving, since I'd just gotten on the freeway), he could not have caught up with me and paced me at that speed in that short distance. I also suggested that a more likely explanation for the ticket was a bumper sticker which identified me as gay, and the fact that I was leaving a (peaceful) civil rights demonstration. (This was in the Midwest, in the 90s.) I was still found guilty, but the full fine and points on my license were not assessed.

Re:Quick summary of TFA

[jeremy85mai]

TL;DR TL;DR: Throw numbers at people who don't understand what the numbers mean, and you can convince anyone of anything

Re:go catch real crooks cops

[mysidia]

I wish cops would just not pick people on the little tiny things and just let things slide, unless its BLOODY obvious.

Running a stop sign is not a tiny little thing. If the officer actually observed the complete failure to properly obey the STOP sign, a ticket should have been issued.

Cars failing to stop ARE a safety issue. And if the law was not being vigorously enforced, there are many jerks on the road purposefully ignoring STOP signs or red lights when they feel they can get away with it -- road safety would be much worse.

Lives are saved when people don't run stop signs because they're afraid of getting a ticket.

Re:I was going to try something similar...

[Mr. Underbridge]

Turns out there was a drug bust in a nearby apartment and they wanted an excuse to search my vehicle. I was sit on a curb with my hands on my head while they searched my car. They couldn't find anything so I was let go without even a ticket.

Um, since when is simple speeding probable cause for a full search of a vehicle?

If they don't ticket you there's nothing to fight so they get away with a blatant breech of the law.

It is even if they do, unless there is something noticeable to justify a search. My guess is they 'asked' you if they could search the vehicle, you were afraid, and you said something that amounted to 'yes'. Should that happen to me, I'll tell them to get a warrant. I'm guessing that if they ask to search the vehicle, they don't have cause and they know it.

Re:No, you don't know if I was "running a stop sig

[ais523]

In the UK, at least, stop signs are incredibly rare. (I live in a major city, and can only think of one, which is on private land not the main road system.) On the other hand, give-way signs (either triangles next to the road, or double-dashed-lines on the ground) are incredibly common; I think those are probably the equivalent of US yield signs, although I'm not sure how direct it is.

And 4-way stops are unheard of; in the UK, if something like that were needed, they'd put a mini-roundabout there instead.

Re:go catch real crooks cops

[Dark$ide]

In the UK all STOP signs are yeild signs, and you can fail your driving test for stopping unnecessarily. UK red lights are the other extreme (there is no 'right on red' allowance), if it's red, you shouldn't pass it except in an emergency.

WTF. That's not true. STOP means stop in the UK. GIVE WAY means yeild.

We'd never have "right on red", we drive on the wrong side of the street over here. Some lights have a left turn filter light (green left arrow that comes on while the main lights are still red).

Re:go catch real crooks cops

[Anonymous Coward]

In PA if the posted speed limit is LESS than 55 MPH you cannot be cited UNLESS your speed was AT LEAST 10mph over the POSTED limit.

Title 75 - VEHICLES
Chapter 33 - Rules of the Road in General
3368 - Speed timing devices.

(4) No person may be convicted upon evidence obtained
through the use of devices authorized by paragraphs (2) and
(3) unless the speed recorded is six or more miles per hour
in excess of the legal speed limit. Furthermore, no person
may be convicted upon evidence obtained through the use of
devices authorized by paragraph (3) in an area where the
legal speed limit is less than 55 miles per hour if the speed
recorded is less than ten miles per hour in excess of the
legal speed limit.

If they ticket you for 5mph over then FIGHT IT.

Oh, and KNOW THE LAW. LEO is last person on earth who you should place any trust in.

Citation please

[stomv]

I don't know how it works in the 1000s of other cities and towns, but in mine THE POLICE DON'T KEEP THE MONEY. The money from ticket revenues goes to the general fund, just like money from other enforcement fines [health dept, building dept, parking enforcement] and other fees [permits, parking, building, etc] and other revenues [property tax, state aid, grants, etc].

I've been involved in local politics for some time, and I've never heard of a police department that kept the ticket revenue. If you know of one, please provide a citation.