GPS vs Radar gun

[+EraSeek]

Read: http://ap.google.com/article/ALeqM5gjiKlNl...zW4zqAespeZ7g7w

 

The service they are refering to gives 30 second readouts they state. However if you are recording to an SD card or using an active track (unsaved) in Garmins all this information is available when you bring it up in Mapsource in shorter and more detailed increments especially if you have selected the "time" setting for recording.

 

Might want to keep your GPS on while driving. ~This is not a way to get around your obligations to traffic laws, but a way to truthfully challenge alledged infractions.

[CoyoteRed]

Petaluma police Lt. John Edwards said he could not discuss Shaun's case but disputed Rude's contention that GPS is more accurate than a speed gun.

 

"GPS works on satellite signals, so you have a delay of some type," Edwards said. "Is it a couple-second delay? A 30-second delay? Because in that time people can speed up, slow down."

 

Obviously Lt. Edwards does not know much out about GPS or physics.

[+Kit Fox]

Several people have won cases, and had their tickets dismissed, using their GPS as proof of their actual speed. I believe this was the first case. GPS Beats Speeding Ticket

[+Sagefox]

But... how clean is your track log?

 

Will it show that two miles back you were doing 16 mph over? Will your top speed recorded be 81 mph?

[+Confucius' Cat]

i have been keeping my track logs on my computer (I use Delorme on a laptop) virtually everywhere i go for several years now.

 

I have long considered that I could use the logs as evidence to beat a bad speeding ticket.

 

I got a ticket about 2 years ago for 79/70. My records and the radar matched exactly. So did the setting of my cruise control. At the time, that was my standard speed on a 70mph interstate. I couldn't imagine a cop writing at that level.

 

I couldn't fight the ticket but I certainly could have certified his radar calibration.

 

I now follow the speed limit meticulously. Especially since I get paid by the HOUR.

 

(boy, does that make the tailgaters mad!)

 

Once in a while, a cop stops the wrong car. The records should be good in that case.

 

The standard for a criminal conviction is "without reasonable doubt." If this standard would be adhered to (questionable in traffic court), then the empirical evidence from the GPS log should be sufficient to beat a ticket. Provided it shows below the speed limit. Speed limit laws are absolute, so if you get a ticket for 70/60 and you testify that you were only doing 61, you are guilty.

Edited October 27, 2007 by Confucius' Cat

[+The Jester]

i have been keeping my track logs on my computer (I use Delorme on a laptop) virtually everywhere i go for several years now.

 

I have long considered that I could use the logs as evidence to beat a bad speeding ticket.

 

I got a ticket about 2 years ago for 79/70. My records and the radar matched exactly. So did the setting of my cruise control. At the time, that was my standard speed on a 70mph interstate. I couldn't imagine a cop writing at that level.

 

I couldn't fight the ticket but I certainly could have certified his radar calibration.

 

I now follow the speed limit meticulously. Especially since I get paid by the HOUR.

 

(boy, does that make the tailgaters mad!)

 

Once in a while, a cop stops the wrong car. The records should be good in that case.

 

The standard for a criminal conviction is "without reasonable doubt." If this standard would be adhered to (questionable in traffic court), then the empirical evidence from the GPS log should be sufficient to beat a ticket. Provided it shows below the speed limit. Speed limit laws are absolute, so if you get a ticket for 70/60 and you testify that you were only doing 61, you are guilty.

Yes, but the fine for 61 is a lot less than the fine for 70. At least here in WA.

[bogleman]

I've been working on a related waymark for Speed Traps - only need one or two more members to get it up and running.

 

Don't let it get as far as a ticket, know where the nasty traps are located and keep the waymarks loaded into your GPS and set the distance warning to 1/4 mile before you hit the trap and get pinched.

[+HB-vanislelady]

I don't know about using this to fight a ticket up here but someone told me that Honda motorcycle speedometers where always out so when I mounted my GPS on the handlebars I did notice that for every ten kilometres in speed my speedometer was a kilometre out...ie..... @ 90k my GPSr stated I was only doing 84k - @ 100k the GPSr said 93k, and so on.....so in that case I would definately try to fight a speeding ticket

[+Seasoned Warrior]

I tend to have a heavy foot and I put on a lot of miles annually, I keep a check on my speed with my GPS but I use my Beltronics radar/laser detector to keep me warned. In CA they must track you at speed for 1000' or more to have a valid ticket. Since most of my route takes me between Los Angeles and San Francisco the range on my radar detector is about 5 miles. Its fun spotting where the radar units are and breaks up an otherwise incredibly boring ride.

[+EraSeek]

I don't know about using this to fight a ticket up here but someone told me that Honda motorcycle speedometers where always out so when I mounted my GPS on the handlebars I did notice that for every ten kilometres in speed my speedometer was a kilometre out...ie..... @ 90k my GPSr stated I was only doing 84k - @ 100k the GPSr said 93k, and so on.....so in that case I would definately try to fight a speeding ticket

 

My odometer/speedometer is off as well in my Honda. I figured when my 100,000 mile warentee expires I will actually only have 99,000 miles or less on the car. I think this is on purpose on the part of car manufacturers.

[+Confucius' Cat]

i have been keeping my track logs on my computer (I use Delorme on a laptop) virtually everywhere i go for several years now.

 

I have long considered that I could use the logs as evidence to beat a bad speeding ticket.

 

I got a ticket about 2 years ago for 79/70. My records and the radar matched exactly. So did the setting of my cruise control. At the time, that was my standard speed on a 70mph interstate. I couldn't imagine a cop writing at that level.

 

I couldn't fight the ticket but I certainly could have certified his radar calibration.

 

I now follow the speed limit meticulously. Especially since I get paid by the HOUR.

 

(boy, does that make the tailgaters mad!)

 

Once in a while, a cop stops the wrong car. The records should be good in that case.

 

The standard for a criminal conviction is "without reasonable doubt." If this standard would be adhered to (questionable in traffic court), then the empirical evidence from the GPS log should be sufficient to beat a ticket. Provided it shows below the speed limit. Speed limit laws are absolute, so if you get a ticket for 70/60 and you testify that you were only doing 61, you are guilty.

Yes, but the fine for 61 is a lot less than the fine for 70. At least here in WA.

True. But the court costs are the same. I think the way our fine schedules goes is something like:

Court costs $150.00 (whether you actually go to court or not)

1-10 over $1

10-20 over $10

20-30 over $100

 

I think it does vary with jurisdictions and the numbers are probably off but the idea is correct. The largest part of the fine is "court costs" and ya gotta pay that for any conviction.

[+Arndtwe]

I tend to have a heavy foot and I put on a lot of miles annually, I keep a check on my speed with my GPS but I use my Beltronics radar/laser detector to keep me warned. In CA they must track you at speed for 1000' or more to have a valid ticket. Since most of my route takes me between Los Angeles and San Francisco the range on my radar detector is about 5 miles. Its fun spotting where the radar units are and breaks up an otherwise incredibly boring ride.

My uncle rides motorcycles and owns a Honda, and he said that his does this too. The reason he said, is so that riders feel like they are going faster than they really are, that way they'll keep their speed down. I don't know how true this is so don't take it to the bank, if you think about it it kinda makes sense.... I guess.

[+Confucius' Cat]

I tend to have a heavy foot and I put on a lot of miles annually, I keep a check on my speed with my GPS but I use my Beltronics radar/laser detector to keep me warned. In CA they must track you at speed for 1000' or more to have a valid ticket. Since most of my route takes me between Los Angeles and San Francisco the range on my radar detector is about 5 miles. Its fun spotting where the radar units are and breaks up an otherwise incredibly boring ride.

My uncle rides motorcycles and owns a Honda, and he said that his does this too. The reason he said, is so that riders feel like they are going faster than they really are, that way they'll keep their speed down. I don't know how true this is so don't take it to the bank, if you think about it it kinda makes sense.... I guess.

I think the term "take it to the bank" is archaic.

Judging from the "sub-prime mortgage crisis," I think "the bank" will accept just about anything nowadays.

 

So will the media, conspiracy nuts, and the rumor mills.

Edited October 28, 2007 by Confucius' Cat

[+Prime Suspect]

But... how clean is your track log?

 

Will it show that two miles back you were doing 16 mph over? Will your top speed recorded be 81 mph?

Doesn't matter. The ticket has to specify exactly where you were caught, and how fast you were going through that specific area is the only thing the court can consider.

[+gorillagal]

i have been keeping my track logs on my computer (I use Delorme on a laptop) virtually everywhere i go for several years now.

 

I have long considered that I could use the logs as evidence to beat a bad speeding ticket.

 

I got a ticket about 2 years ago for 79/70. My records and the radar matched exactly. So did the setting of my cruise control. At the time, that was my standard speed on a 70mph interstate. I couldn't imagine a cop writing at that level.

 

I couldn't fight the ticket but I certainly could have certified his radar calibration.

 

I now follow the speed limit meticulously. Especially since I get paid by the HOUR.

 

(boy, does that make the tailgaters mad!)

 

Once in a while, a cop stops the wrong car. The records should be good in that case.

 

The standard for a criminal conviction is "without reasonable doubt." If this standard would be adhered to (questionable in traffic court), then the empirical evidence from the GPS log should be sufficient to beat a ticket. Provided it shows below the speed limit. Speed limit laws are absolute, so if you get a ticket for 70/60 and you testify that you were only doing 61, you are guilty.

Yes, but the fine for 61 is a lot less than the fine for 70. At least here in WA.

True. But the court costs are the same. I think the way our fine schedules goes is something like:

Court costs $150.00 (whether you actually go to court or not)

1-10 over $1

10-20 over $10

20-30 over $100

 

I think it does vary with jurisdictions and the numbers are probably off but the idea is correct. The largest part of the fine is "court costs" and ya gotta pay that for any conviction.

 

Here in Colorado Springs, the court costs are pretty low (I think $20-$30), but fine is $10 for each mile per hour over the speed limit. So here, a few miles per hour makes a big difference in cost.

[+DonB]

I've been working on a related waymark for Speed Traps - only need one or two more members to get it up and running.

 

Don't let it get as far as a ticket, know where the nasty traps are located and keep the waymarks loaded into your GPS and set the distance warning to 1/4 mile before you hit the trap and get pinched.

At one time there was a website, speedtrap.com. I don't know if they're still around or not.

[+Team_LPD]

Devices used by the PD must be calibrated and documented, including the training to use them. These devices usually have a built in fudge factor that benefits the driver, not the police.

 

GPSr's have no calibration or documentation to verify their accuracy. Most civilian GPS units have an accuracy of +/- 15 feet or so.

[+Prime Suspect]

Devices used by the PD must be calibrated and documented, including the training to use them. These devices usually have a built in fudge factor that benefits the driver, not the police.

 

GPSr's have no calibration or documentation to verify their accuracy. Most civilian GPS units have an accuracy of +/- 15 feet or so.

That "accuracy" is based on determining a specific location. A GPS doesn't bother with location in determining speed. Instead, it uses the far more accurate method of detecting Doppler shift. This has an accuracy of ±½MPH.

[+EraSeek]

Devices used by the PD must be calibrated and documented, including the training to use them. These devices usually have a built in fudge factor that benefits the driver, not the police.

 

GPSr's have no calibration or documentation to verify their accuracy. Most civilian GPS units have an accuracy of +/- 15 feet or so.

 

On the GPS end, that's not quite true. GPS's are continuely "calibrated" (and updated every second). It recieves almanac updates every 12.5 minutes as I recall and less than that on WAAS. A GPS is really a timing device. If the timing is off by one nanosecond (one billionth of a second) it throws your position off by one foot. The errors and delays are both internally corrected in firmware and externally with WAAS. What is important here is not position so much, but speed. The manual on all my GPS's say the velocity accuracy is either 0.05 meters/sec steady state, or 0.1 knot RMS steady state.

[+Confucius' Cat]

Devices used by the PD must be calibrated and documented, including the training to use them. These devices usually have a built in fudge factor that benefits the driver, not the police.

 

GPSr's have no calibration or documentation to verify their accuracy. Most civilian GPS units have an accuracy of +/- 15 feet or so.

Fair enough, but all it SHOULD take is a reasonable doubt to get an acquittal. Depending on the judge, this doubt COULD be because the civilian unit showed a few mph less than the radar. Depending on the judge, it COULD be enough to throw the case out, rather than just reduce the fine to match what the defendant admitted to. (Theory: if something is proven to be inaccurate, from that point forward it's "testimony" is by definition, moot)

 

Most judges i watched 9and brought cases before) when I was a cop would always say "guilty on your own admission" if one were to argue they were not speeding AS MUCH as the cop said.

 

In practice, I have seen few speeding cases won by defendants. About the only ones I have heard of lately have been a spate (maybe better said RASH) of incidents (reported in the news a while back) where the officer does not show up. Without a doubt, this is the most likely means of beating a speeding ticket. I have seen it on some web sites that they would advise you to always go to court, because the officer missing court is very common and in most states you have nothing to lose but your time.

 

On a slightly different note, I once wrote two identical tickets for "improper start" to two different teenagers for the same incident in a school parking lot. I noted on the ticket that one of them had said something "smart" before he peeled out in front of me (it has been a long time ago- memory) and the other one had not said anything I had heard but peeled out after the first one. The boy who i had not heard say anything went first in front of the judge, talked to the judge very respectfully, and gave a typical excuse "there was loose gravel there." The judge dismissed his case.

 

The second boy got up and started in about how I was unfair and had no right to write him a ticket and I was "just looking for something to harass him for" when he just accidentally peeled out in the "loose gravel" (OBTW it was an asphalt parking lot) the boy's tone of voice was obviously vindictive. His father had given me (and the judge) the 'what-for" too.

 

The prosecutor recommended dismissal since the loose gravel was probably the reason for the offense.

 

The judge however, said "uh-uh" this is a totally different situation... I can tell from this boy's and his father's attitude that he did this deliberately..." maximum fine and costs.

 

Point is- traffic court is unique. Speeding tickets are hard to beat. The rules of reasonable doubt may not apply and accuracy COULD become a big debate but it is not really likely. It has been my experience in traffic court that the judge pretty much "rules the roost."

 

For the most part it is simple economics-

 

* most people don't bother fighting speeding tickets at all because it costs less overall just to pay the fine.

* there is not enough money involved to be worth an appeal

* generally, it is not even enough money involved to be worth hiring a lawyer

* without a lawyer, you are likely going to "hang yourself"

 

Therefore the "you can't fight city hall" adage generally applies and your GPS probably won't beat a ticket unless you can use it to clearly show that the cop pulled over the wrong car.

[+Sileny Jizda]

You are looking for http://www.speedtrap.org for the website. It still exists and is quite useful in avoiding over-zealous officers looking for a few tickets for their next performance review.

Edited October 29, 2007 by Sileny Jizda