Radar Wins Speed Test Against GPS

Radar may be More accurate But it is also Misused, abused, and has also been proven to be wrong. I have seen them clock trees at 35 mph.
I also have seen glitches In GPS speeds..But for the Most part they are also Very accurate.. this case Might have been interesting if the company that Made and Sold this unit that was in the Kids car would have been in the courtroom. I am surprised they were not with the implications of this case.

I agree, gsp can be very accurate, I rely on it heavier then my speedometer, but against radar, I would have to side with radar (I can't believe I said that!)

Proving that the GPS system is accurate should not have been a hard task. That doesn't automatically make radar wrong because both are very accurate devices. The discrepancy is the user of the radar gun. They are human and subject to errors and cheating so in my opinion they are always suspect.

The speed on my GPS does not seem very accurate it shows my fastest speed as 197mph in a truck governed at 67.

I suppose it depends on the GPS being used and the comparative margin of error on the GPS vs the margin for error on the Radar.

I wonder what the speed the GPS actually clocked him at.

It would be interesting to know how the kids speedometer compares to the gps system in his car. I doubt that he was watching the gps at the time. In some states you can win in court if you have your speedo checked and its found to be off. Anyway I agree with Asianfire about the human error aspect.
And Tselby...you have a big problem...lol

PS: I love the video here of the guy on the airplane with a gps showing him going 564 mph..how cool is that?

I agree that GPS isn't perfect as a speed measuring device. However, the discrepancy is 17 mph (62 in a 45 zone) in this case. That's a pretty big difference, and I'd like to think that my GPS is accurate to within 17mph at least 99.99% of the time. Sure, glitches happen every once in a great while.. but what are the chances that the GPS was inaccurately reporting his speed for the entire length of the section of road he was on? On the other hand, the laser, while having a good track record of accuracy, could have been aimed badly, or miscalibrated, etc.

I don't know, sounds to me like the judge sided with the technology he was comfortable with, rather than what made sense. Then again, maybe the defense did a shoddy job of making a case in the first place.

radar is very accurate, however, as you stated, human error is a huge factor. The radar can tell you how fast something is moving, but it can tell you what is moving that fast. The LEO has to determine that himself. Now that isnt hard if you are the only one on the road or you are the first to come around a bend, but other then that, it is very difficult to know which car is really going the speed that the radar states. Radar reading can be off because of the way the LEO is positioned relative to the target, but that is to the target car's advantage. In other words, the radar reading will be lower then actual speed of car.

I have found that the GPS is much more accurate then my spedo as it takes into account tire wear etc. To the contrary, radar has failed many times. I would want to see when the radar equipment was last calibrated etc.

My two cents

Yeah that is one of the things I always question, the LEO says that he calibrated it before he went on duty, but I wonder how many times that is really true. What do you mean that radar failed many times?

I vote for the GPS in overall accuracy. However, the radar is of greater familiarity with the court. When one takes a case to court, and both sides have good merit, a decision still has to be reached. The deciding factors are not always as clear-cut as the court would wish.

Here is the thing, GPS isn't an approved speed measuring device, so even if it is more accurate (and I am not saying that it is or isn't) radar, it still can't be held in the same respect as police radar.

Whatever happened to reasonable doubt? Sounds like we have it right here...

Traffic cases are decided on preponderance of evidence, not reasonable doubt. The decision is based upon superiority in weight, power, numbers, etc. of the evidence. As was posted earlier, radar familiarity to the court, the number of cases decided with radar, etc, tend to make that a more powerful argument.

I find that when driving by a radar speed display, my GPS is spot on to the displayed speed where my speedometer is not that accurate. I always set my cruise control while on the highway based on the GPS speed rather than the speedometer.

Bill

From the article it appears as this GPS was not ones that "we" normally use, but one that does tracking to be downloaded later and reviewed.

There are many commercial companies that will log every so many seconds speed lat long and write it to a file. This file is then sent "over the air" back to a computer or manually downloaded from the truck. Most units have no display and lots of drivers don't even know they are there.

So he should have had a file of time line history, but if it only polls every 30 sec or more, I could see where they could throw it out of court. 17 mph is a big jump though...and I'm sure we don't know the "rest of the story!"

Daniel

Am I missing something - even if the GPS is more accurate or equal - how do you prove to the court you are right and an officer of the court is wrong. You have every incentive to misstate. Why not just say my speedometer says I was doing 35mph?
But then again just because you are paranoid doesn't mean people aren't out to get you.

If you have a log file that shows from 9:30 to 9:40 am you were only going 42 mph, and the officer says I got you on radar at 9:36 doing 63, then you should be able to prove your case. The court said a gps log isn't allowed as it is "new tech." It was a way to help say I was only going 42 on my speedOmeter.

daniel

My vote is for the kid having reset the maximum speed value then driving around the block to set it to a reasonable number. Then he gets home and cries that he did nothing wrong not suspecting the old man would actually take it to court. He was probably just trying to get around a good ass kicking....