Question about Police Lidar Standard Deviations

Page 6 - Seeking answers? Join the AnandTech community: where nearly half-a-million members share solutions and discuss the latest tech.

waggy

No Lifer
Dec 14, 2000
68,145
10
81
LOL great thread.

there are ways to contest a ticket. this tactic is not one of them.
 

Paladin3

Diamond Member
Mar 5, 2004
4,933
877
126
Using my example, it will still be 100% ticketed. Lets put it in simpler terms.

Let's say OTC pregnancy tests have a 5% chance to give a false positive. If 100 infertile women took the test, on average, five would show a false positive. In this case, 100% of those who had a positive result aren't really pregnant.

Terrible analogy. This argument hinges on it being impossible that you were speeding. That you are one of the "infertile" group and that any positive result is automatically false. You can't prove that, and, in fact, the preponderance of the evidence says otherwise.

You are so desperate for your "research" to fit your preconceived conclusion that you aren't thinking logically. Get a grip, my friend.

EDIT: ...or exactly what JEDIYoda said.
 
Last edited:

Paladin3

Diamond Member
Mar 5, 2004
4,933
877
126
Glad you realized this. Now let's move one step further, slowly so you can understand. A cop LIDAR's 100 people. 5 were going above the speed limit. 95 were going at the speed limit. There is a 1% chance the device records someone going 10 mph faster than they actually were going. On average, what % of the ticketed drivers were going at the speed limit?

Again, what does this have to do with YOUR case? How can you prove you are the 1% (and it appears the LIDAR devices don't have anything even close to that level of inaccuracy) that the gun got wrong?

Just because it is very, very remotely possible doesn't mean it is likely or a good defense in court. The evidence against you is soooooo much more compelling. Good luck in court and don't forget your checkbook.
 

Geforce man

Golden Member
Oct 12, 2004
1,734
7
81
Thanks for the response. I won't attempt to prove that the device was defective. A device can be working perfectly with no operator error and ideal conditions, and still return a reading that is wrong!

I just need the data above to prove my point. With this data, I can point out that if an officer takes X measurements in a year, he will have Y false positives. I have more but that's the beginning.

First: will admit, didn't read whole thread (shame on me)

To what another poster said...

The machines are not "Calibrated" daily, they are checked for calibration. This is a process that is well documented, easily reproducible, and low likelihood of error. If the officer finds that the machine isn't calibrated per testing, then he/she will likely not use it.

To the OP:

If we are talking a RADAR type system, you won't find much. These things have been in existence for years, and there is a lot of scientific evidence to back them up. What you will find, is that lawyers initially tried as you did, to prove that they are wrong or produced an inaccurate reading. What they found, is that if they were in error, they were in error to the benefit of the speeder showing lower speeds than what the speeder was doing if anything.

There is also a strong possibility he/she used a laser system, as well. These are basically perfect. This technology has also been around for quite some time, and is specifically targeted, by a laser. If the officer checked the machine at all, and it provided him with the correct readings upon checkout, you're just wrong.

Not to be a debbie downer. Sorry sir.
 
Last edited:
Feb 4, 2009
34,703
15,951
136
OP I'm a bit confused are you saying you were going 55 in a 55 mph zone and they read you at 73 mph in error or are you saying you were going 65 in a 55 mph zone and it read 73 mph in error?
 

GagHalfrunt

Lifer
Apr 19, 2001
25,297
2,001
126
Just because it is very, very remotely possible doesn't mean it is likely or a good defense in court. The evidence against you is soooooo much more compelling. Good luck in court and don't forget your checkbook.

That's just terrible advice. No real man meekly writes a check when he's been so seriously wronged.

OP. leave your checkbook home. If the judge won't listen to reason you have other options. This is a much bigger issue than a few dollars in road use tax. You're right, they're wrong and this is America damnit!! You stand right there in the court and you refuse to pay, you refuse to leave and you refuse to be silenced. You have rights and you make damn sure the court knows you're aware of those rights. It's the only way they'll respect you.
 

PJFrylar

Senior member
Apr 17, 2016
974
617
136
Terrible analogy. This argument hinges on it being impossible that you were speeding. That you are one of the "infertile" group and that any positive result is automatically false. You can't prove that, and, in fact, the preponderance of the evidence says otherwise.

You are so desperate for your "research" to fit your preconceived conclusion that you aren't thinking logically. Get a grip, my friend.

EDIT: ...or exactly what JEDIYoda said.

Either that or the OP is just trolling. You would think that a reasonable person, even when caught in the process of grasping at straws like the OP is, would see his argument is unanimously disagreed with for a myriad of reasons and realize the argument is stupid. Especially in the context of traffic court where it doesn't matter if he's right or not, because it is more likely he's not.
 

DrPizza

Administrator Elite Member Goat Whisperer
Mar 5, 2001
49,606
166
111
www.slatebrookfarm.com
OP I'm a bit confused are you saying you were going 55 in a 55 mph zone and they read you at 73 mph in error or are you saying you were going 65 in a 55 mph zone and it read 73 mph in error?
Upon close inspection of the thread, you'll see that the OP said he doesn't know how fast he was going, but the LIDAR must be wrong, because he never speeds on that road. Thus, he wants to prove to the judge that the LIDAR is incorrect one out of every eleventy-billion times, and he's the eleventy-billionth person to get a speeding ticket, therefore he wasn't speeding.
 
Feb 4, 2009
34,703
15,951
136
Upon close inspection of the thread, you'll see that the OP said he doesn't know how fast he was going, but the LIDAR must be wrong, because he never speeds on that road. Thus, he wants to prove to the judge that the LIDAR is incorrect one out of every eleventy-billion times, and he's the eleventy-billionth person to get a speeding ticket, therefore he wasn't speeding.

Thanks that explains why I was so confused.
 

Hacp

Lifer
Jun 8, 2005
13,923
2
81
And you are GREATLY overstating the inaccuracy of LIDAR's measurements.

I have not overstated anything. I have given examples using dummy numbers in absence of data. These are dummy numbers that will be filled in if/once I get the actual data. If the data shows that an officer won't get a single false positive in a year, I won't use the argument. If the data shows an officer gets one false positive a week then I can bring the argument up. Make sense?
 

Carson Dyle

Diamond Member
Jul 2, 2012
8,174
524
126
When is your court date? The actual account of your 45 second hearing should be humorous. I'm sure you'll be outraged, but maybe you'll be able to appeal it up to the US Supreme Court and finally get some justice. For your speeding ticket.
 

Hacp

Lifer
Jun 8, 2005
13,923
2
81
When is your court date?

Thanks for your concern. Finally a positive statement!

I have not set up a court date. I have 15 days to decide whether I want to go to court or not. It costs 25 dollars and that won't be refunded even if I win. I need to spend this time refining my defense. When it is good enough, I will mail in the ticket and get a court date.
 

zinfamous

No Lifer
Jul 12, 2006
110,806
29,557
146
Another piece of evidence to add to my list. Law enforcement regularly overstates the certainty in forensics/measurements. The trust me argument won't work anymore.

http://www.nytimes.com/2016/06/04/u...t&contentPlacement=8&pgtype=sectionfront&_r=0

I like this angle.

So are you going to submit a cleverly-constructed lineup of hair follicles and fibers, ballistics evidence with spent casings, and fingerprints?

This is great.

By the way--it's alctually been long-known that this type of classic evidence has been full of bunk...I just don't see what it has to do with your traffic ticket.

The problem with this evidence is about drawing connections where none exist: comparing two fibers without a real control sample to distinguish fibers, for example (the testing methodology for this and ballistics has always been pure shit, but cases are constructed in such a way that a prosecutor need only hire an "Expert" to "expertly" convince the jury that their "expertise" in this "experty" craft of comparing random samples without valid methods is beyond reproach.)

This isn't the same problem with a testable, repeatable, provable measuring device like Lidar. You might as well grab a laser surface thermometer and claim that it's measuring 75.6 F when another tool measures 75.2 is some a grand flaw.
 

zinfamous

No Lifer
Jul 12, 2006
110,806
29,557
146
Terrible analogy. This argument hinges on it being impossible that you were speeding. That you are one of the "infertile" group and that any positive result is automatically false. You can't prove that, and, in fact, the preponderance of the evidence says otherwise.

You are so desperate for your "research" to fit your preconceived conclusion that you aren't thinking logically. Get a grip, my friend.

EDIT: ...or exactly what JEDIYoda said.

This is called finding evidence to support a conclusion.

OP strikes me as an engineer-type, but a piss poor scientist. Sadly, that seems to be way more common than it should be.
 

zinfamous

No Lifer
Jul 12, 2006
110,806
29,557
146
Either that or the OP is just trolling. You would think that a reasonable person, even when caught in the process of grasping at straws like the OP is, would see his argument is unanimously disagreed with for a myriad of reasons and realize the argument is stupid. Especially in the context of traffic court where it doesn't matter if he's right or not, because it is more likely he's not.

Are you just an ATOT newb, or an internet newb in general?



Anyway, welcome and enjoy the forums. Don't touch the potato salad (Boomer made it)
 

zinfamous

No Lifer
Jul 12, 2006
110,806
29,557
146
Thanks for your concern. Finally a positive statement!

I have not set up a court date. I have 15 days to decide whether I want to go to court or not. It costs 25 dollars and that won't be refunded even if I win. I need to spend this time refining my defense. When it is good enough, I will mail in the ticket and get a court date.

Ah, I see.

AT: we need to help OP refine his defense. I'm going to scour the internet for additional LIDAR data.

:thumbsup:

In the meantime, have you considered bringing up a tireprint challenge? Did the ticketing officer take a record of your tire treads and if not, how can he prove that the car he ticketed was your car?
 

Hacp

Lifer
Jun 8, 2005
13,923
2
81
This isn't the same problem with a testable, repeatable, provable measuring device like Lidar. You might as well grab a laser surface thermometer and claim that it's measuring 75.6 F when another tool measures 75.2 is some a grand flaw.

DNA test, hair analysis,and fingerprinting matching satisfy these requirements. You haven't added anything new.
 

Hacp

Lifer
Jun 8, 2005
13,923
2
81
In the meantime, have you considered bringing up a tireprint challenge? Did the ticketing officer take a record of your tire treads and if not, how can he prove that the car he ticketed was your car?

Sorry but that is not part of my argument. If you want to do the work and write up a detailed five minute script to send me, be my guest. I'll take a look and at least consider it.
 

zinfamous

No Lifer
Jul 12, 2006
110,806
29,557
146
DNA test, hair analysis,and fingerprinting matching satisfy these requirements. You haven't added anything new.

DNA, yes, absolutely.

hair and fingerprint, no. Or did you actually read the article that you posted?

hair/fiber matching and fingerprinting has long been rife with errors. It really isn't repeatable or provable. Like I said, for such evidence to fly, it requires an "expert witness" in court to testify about their expertness in the skills to make such claims, and thus convince the jury that their expertness determines the validity of these tests.

That is exactly what you were criticizing, and trying to point towards your LIDAR scheme. But it doesn't make sense, because LIDAR is like DNA--it is a measured, irrefutable record.

DNA paternity tests have a ~98% accuracy rate. Identity testing is even better. Perhaps you still need a "DNA expert" to explain this to juries, but they have numbers and thousands upon thousands upon thousands of validity tests with DNA to show the low margin of error.

With fiber/ballistic matching, or fingerprints, you have no real tests. No numbers: you produce charts that show 10-40x images with little measure bars. You never talk about error rates and the testing methodology with these. Never.

There is a reason lie detectors are not admissible in court: it isn't science. Law is only now coming around to the understanding that this kind of evidence is completely flawed. I say the understanding....I doubt that police and prosecutors are anywhere near accepting these flaws, and you will still see this garbage as evidence.

...but that's a digression. ....I guess I'm confused as to why you would argue against the very argument that you presented earlier. :hmm:
 

zinfamous

No Lifer
Jul 12, 2006
110,806
29,557
146
Sorry but that is not part of my argument. If you want to do the work and write up a detailed five minute script to send me, be my guest. I'll take a look and at least consider it.

I don't have access to your car. I would suggest snapping some photos of at least 3 angles, glossy 8x11s, with blow up images of 3 detail regions on each shot. Be sure to include arrows and short paragraphs describing each figure and each detail blowup on the back of the photo.

You call them figure 1a-c; fig 2a-c; fig3a-c. each figure and subfigure needs its own caption on the back of the photos.

All you really need to do is present this evidence, and ask if the ticketing officer (if he or she shows), has similar or even identical photo evidence. That should only take 5 seconds of your time (you only need to go into the figure detail if the officer has their own tire evidence).

The thing is in the details: You show the judge your effort to provide factual evidence in defending your innocence, then they can't help but be swayed by your profound thirst for justice.
 

Hacp

Lifer
Jun 8, 2005
13,923
2
81
With fiber/ballistic matching, or fingerprints, you have no real tests. No numbers: you produce charts that show 10-40x images with little measure bars. You never talk about error rates and the testing methodology with these. Never.

It looks like you're talking about the OLD way people matched finger prints, which was by eye inspection. Sorry to burst your bubble but there is software out there that can read fingerprints and match them. The method used is a form of pattern recognition.
 

zinfamous

No Lifer
Jul 12, 2006
110,806
29,557
146
It looks like you're talking about the OLD way people matched finger prints, which was by eye inspection. Sorry to burst your bubble but there is software out there that can read fingerprints and match them. The method used is a form of pattern recognition.

I'm aware of that. The point here is that pattern recognition as evidence is the problem. Fingerprints really aren't as unique as believed.

The "ID points" used in these algorithms are actually rather arbitrary. It is why this really isn't evidence.

It is the same as arguing that the chamber marks from this bullet casing fired from this gun mean that only the suspects gun could have ever fired these exact casings--nevermind that thousands of people own that very same gun with those very same bullets because there really isn't much variety in this type of manufacturing. All it takes is that "expert" to convince a pool of people that they are expert enough to make those claims. These are situations where more data is actually bad for you.

Again, not sure why you would first present these flaws in police investigation as a pillar of your defense, then turn around and defend the very same techniques.
 
sale-70-410-exam    | Exam-200-125-pdf    | we-sale-70-410-exam    | hot-sale-70-410-exam    | Latest-exam-700-603-Dumps    | Dumps-98-363-exams-date    | Certs-200-125-date    | Dumps-300-075-exams-date    | hot-sale-book-C8010-726-book    | Hot-Sale-200-310-Exam    | Exam-Description-200-310-dumps?    | hot-sale-book-200-125-book    | Latest-Updated-300-209-Exam    | Dumps-210-260-exams-date    | Download-200-125-Exam-PDF    | Exam-Description-300-101-dumps    | Certs-300-101-date    | Hot-Sale-300-075-Exam    | Latest-exam-200-125-Dumps    | Exam-Description-200-125-dumps    | Latest-Updated-300-075-Exam    | hot-sale-book-210-260-book    | Dumps-200-901-exams-date    | Certs-200-901-date    | Latest-exam-1Z0-062-Dumps    | Hot-Sale-1Z0-062-Exam    | Certs-CSSLP-date    | 100%-Pass-70-383-Exams    | Latest-JN0-360-real-exam-questions    | 100%-Pass-4A0-100-Real-Exam-Questions    | Dumps-300-135-exams-date    | Passed-200-105-Tech-Exams    | Latest-Updated-200-310-Exam    | Download-300-070-Exam-PDF    | Hot-Sale-JN0-360-Exam    | 100%-Pass-JN0-360-Exams    | 100%-Pass-JN0-360-Real-Exam-Questions    | Dumps-JN0-360-exams-date    | Exam-Description-1Z0-876-dumps    | Latest-exam-1Z0-876-Dumps    | Dumps-HPE0-Y53-exams-date    | 2017-Latest-HPE0-Y53-Exam    | 100%-Pass-HPE0-Y53-Real-Exam-Questions    | Pass-4A0-100-Exam    | Latest-4A0-100-Questions    | Dumps-98-365-exams-date    | 2017-Latest-98-365-Exam    | 100%-Pass-VCS-254-Exams    | 2017-Latest-VCS-273-Exam    | Dumps-200-355-exams-date    | 2017-Latest-300-320-Exam    | Pass-300-101-Exam    | 100%-Pass-300-115-Exams    |
http://www.portvapes.co.uk/    | http://www.portvapes.co.uk/    |