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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."
We only have his word that he actually stopped. It would be more correct to say that another car explains why there are multiple scenarios explaining what the officer thought he saw. The only way this really relates to traffic (or other) laws is that western law specifically handles multiple scenarios by stating that the burden of proof is on the accuser to show that the scenario they outlined meets a requisite threshold. Physics is not trumping anything, it merely allows one to illustrate in this case some of those alternatives.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
The vast majority of stop signs are stupid and should be replaced with yield signs.
by stating that the burden of proof is on the accuser to show that the scenario they outlined meets a requisite threshold
That threshold, in traffic court, is usually just the officer saying so... not actually proving it. So in this case physics effectively trumped SOP.
Are you sure this isn't a plot line the Big Bang Sitcom?
No. This story is vaguely interesting.
sustainable living
Cry me a river. Tell them to be big girls, and cough up some objective evidence.
Tired of this constant bullsh*t in traffic court.
I am John Hurt.
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).
The officer didn't observe him not stopping at the stop sign. The officer ASSUMED he did not stop based on the state of the car he observed before his was obstructed, and the state of the car he observed after it was no longer obstructed.
The officer should be disciplined for taking that shortcut and citing based on a supposed occurence that were not actually directly observed.
No, they'd spend 15s a day pushing the timestamp button, which each time would automatically attach the previous 30s of video to the electronic record for the citation.
Just because something would be time consuming to do with the *current* equipment doesn't mean that it would be time consuming with *proper* equipment.
Can you be Even More Awesome?!
This argument is a shameless piece of sophistry.
It's central argument is "I did stop; a car just passed in front of me and you didn't see.". This is then expanded into 4 pages of unnecessary and probably disingenuous over-analysis.
The entire argument breaks down in FIG 5. Leaving aside this nonsense of measuring angular speed(The human brain interpolates just fine), the author compares two curves in which the equated angular speeds of the car do not translate into the same linear speed. Indeed, at the occlusion point at t~1.5 s, the car corressponding to the blue curve would be travelling at 15m/s, verses the car at constant 8m/s that it is being compared to.
And this is even before we begin talking about how the author is really comparing a car at constant speed to one which reverses back into the stop sign and then drives forward.
I think this kind of thing is described as "sophomoric", and in that that word describes a second year student who is full of their own knowledge with no concept of their own ignorance, I would have to label it as such. The cop was right, pay your ticket Mr. Krioukov, and don't darken the door of the maths department for a very long time.
May the Maths Be with you!
Which just proves that in many cases tickets are more of a revenue source than they are an enforcement mechanism.
Also the reason why they like to screw with yellow lights to make it harder to stop in time.
I tried to argue a reckless driving ticket using math and physics when I was younger. I was in the right and proved it conclusively based on the officers statement, but the back-woods judge just changed the charge to a misdemeanor and fined me anyhow for "anything you might have done in my county". When I asked about appealing his decision, the judge pointed out that it would cost $300 and him being the only judge, he'd probably say the same thing next time. If the court's looking to collect some money, the court's going to collect that money one way or another.
- tensions in our lives that are attacking our minds, unite themselves together to make our consciousness blind - op'ivy
Traffic cop is ultimately one of the most important law enforcement jobs in America. They serve more arrest warrants than anybody else and are the ones most likely to be visible to the population at large. Now, if the officer didn't see the car drive through without stopping, then the ticket shouldn't have been issued.
Are you suggesting that the modding system isn't free speech? You're allowed to say it, we're allowed to tell you to eff off, you vile, odious racist.
Got them moderator blues I blieve I walk out the do', With these mod-points I been gettin', I 'most never post no mo'
of arguing "I did stop, but the officer's view was obstructed by another vehicle and hence he couldn't have seen whether I did or did not" and having the officer agree that his view was obstructed.
I did the same thing with my seatbelt once. The officer told me "I have no proof you were wearing a seatbelt; I didn't see you wearing one." Apparently he didn't need proof I wasn't... I wasted a day getting it thrown out in court.
By his graph, it looks like he's saying that he waited until almost at the stop sign, sneezed and slammed on the brakes, came to a stop of zero duration while obscured behind another car stopped at the stop sign, then gunned it to cross the intersection.
And that the officer totally missed the difference in position between a car that sails through an intersection as opposed to one that both decelerates to a full stop and accelerates fully up to speed over a period of about 3 seconds,
Hmmm. Maybe...
But I'd really like to see this demonstrated. It would make an interesting project. Mythbusters?
I wish cops would just not pick people on the little tiny things and just let things slide, unless its BLOODY obvious.
Cops shouldn't let things slide they should just be more certain when they issue a ticket. IE they should not make an assumption about a violation, they should actually witness it (or get testimony from a witness). Ever been driving and wonder if someone on a cross street is going to stop? Unwittingly, many people that roll stop signs slow down cross traffic resulting in delaying when the 'roller' would be able to pull out if they had just stop so everyone knows what they are doing. People who only use their blinker 'when necessary' never see the person they nearly hit because no one knew what the hell they were doing.
Its way overdue for teachers to be obsolete, except helping the 'challenged' few, s burn those text books, put all courses online and exams online, and marking online, what a teachers for again? Keeping the peace? taking roll calls?
Making sure YOU took the test.
Without the maths, the defence is "I actually did stop briefly, but your view was obscured by another car". I would hope that in the interests of justice the simple version would also lead to an acquittal, the judge realising that if the police couldn't see the car at the time there is reasonable doubt. I expect it was more of a case of "wer'e not going to pay for a mathematician to support the prosecution on a trivial case like this.
In the UAE, all stop signs are treated like yield signs by the drivers... but there are not really 4 way intersections an when there are, they are in construction zones with no traffic volume - it's like a dangerous 4 way yeild and the intersection gets closed until they put up traffic signals. I don't think the accident rate at stop signs are any higher here than in North America, but I'd love to see some real data.
120 characters ought to be enough for anyone
And that the officer totally missed the difference in position between a car that sails through an intersection as opposed to one that both decelerates to a full stop and accelerates fully up to speed over a period of about 3 seconds,
I wondered if someone would bring that up. The angular velocity profiles might look similar during the non-obstructed portions, but their integral will not. Could be that a clever prof just used physics to confuse the crap out of a layperson and get out of a "California stop" (ie, a little flash of red tail light, and proceed on your way) ?
But many of these cases are moving violations and not subject to jury trials. How do would one go about doing what you say in those cases?
Laws of Physics were declared unconstitutional by their state supreme court, along with evolution.
They serve more arrest warrants than anybody else and are the ones most likely to be visible to the population at large.
That is only because the police refuse to put any real resources into investigating *real* crimes like theft and vandalism. If the police took all of their traffic cops and put them on investigating property crimes instead, there would be a huge decrease in property crimes and we could start putting people in jail for real crimes for a change. How many times have you heard about a friend whos home or car got broken into? These criminals are not brain surgeons. They leave tremendous amounts of evidence behind, but the police dont even bother to collect any of it, much less investigate. My car was broken into a few years back, and the perpetrator left about 50 full prints behind. The cops wouldn't even show up (took a statement over the phone!). My wife was a criminal justice student at the time and had access to a fingerprinting lab. After lifting about 3 dozen prints, a friend of ours in the DCJS ran the prints through the database (only a minor violation...), and sure enough out pops a guy we've never met. Had three prior convictions for drug related charges, and one grand theft! This was strike four, and the guy would have been off the streets for good, but the cops failed completely.
Long Story short, the police need to stop worrying about traffic tickets so much, and start doing actual criminal investigations. At any given point, how many cops are tied up in speeding traps? How many real crimes could be solved if those cops were to spend their time investigating instead of sitting in a parked car...
-=Geoskd
I wish I had a good sig, but all the good ones are copyrighted
While I agree with you about inappropriate policing priorities, I have to say I find your actions in abusing privileged access to a database to be more offensive than those of the person who broke into your car. Your friend at the DCJS who committed that "minor violation" should have been fired and prosecuted. The fact that you were right in the end does not justify the means, and we must never allow that kind of rationalisation to excuse abuse of public trust when officials have access to sensitive personal information.
If you disagree, post your argument. (-1, Overrated) isn't your personal censorship tool for views you don't like.
I figure that even if some of the points are technically accurate, they're presented with one hell of a slant.
Yep, it's offtopic - zealots have a habit of doing that - out of enthusiasm, jamming stuff in where it doesn't really fit the discussion.
I listen to both RIAA and non-RIAA stuff if I like the music, tangential business/politics nonwithstanding.
The problem with his partially blocked view defense is he's claiming that his Yaris, is capable of over 1G accelleration from a stop. (10 m/s^2 is more than 9.8 m/s^2). That is supercar like acceleration, even to maintain only up to 20 MPH.
His whole paper is based on breaking the laws of physics for his Yaris, and hiding it so that the judge and officer don't notice.
Considering that the crux of his argument (ignoring the smoke and mirrors angular velocity aside), was that he claimed he stopped and then accelerated back to the same speed as before all while he was hidden behind the other car, yes, it really matters. You fell for the same thing the judge did. The verbosity of the whole thing was all designed to hide the core claim, which is what I have said here.