Technology as a defense against speeding | GTAMotorcycle.com

Technology as a defense against speeding

TwistedKestrel

TwistedKestrel

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Another thread got me wondering about how much weight technology would have as a defense against speeding, in today's courts. I know in the past people have produced GPS logs, video footage, etc to disprove allegations of speeding, but what specifically would the court take seriously today, and what would they ignore? For example, would traffic court entertain footage from a GPS-enabled dashcam? What would be the best case scenario (besides not driving/using technology to prove you weren't driving). I'm hoping for Rob to weigh in on this.
 
Courts will not entertain GPS logs, because a GPS it is not designed to accurately measure your speed. Law enforcement's speed measuring device is however designed to measure speed; it also has testing mechanisms, and checklists to make sure it's working in proper order.

If you had a calibrated/certified speedometer from measurement canada, and in-car video of your speedometer that would be something. You would also have to testify to making sure your tire pressures were at the manufacturer suggested range. You yourself may need to make some sort of notation of when you last checked this.

The courts would have to then look at both technologies, calibrated tire pressure + speedometer vs. lidar reading; they would have to choose which one is the most reliable.

The speed difference between the two technologies should not be that great, keep in mind this is also why law enforcement give drivers a generous buffer due to inaccurate speedometers.

R. v. Anghel, 2010 ONCJ 652 (CanLII)

THE DEFENDANT’S EVIDENCE: The defendant, Mr. Danut Anghel, gave evidence. In his examination-in-chief he told the Court that he and his wife were travelling back home to Toronto from Tobermory. He said they were stopped by the police officer and their car was impounded because the officer said they were speeding at 134 kilometres an hour. Mr. Anghel said that he tried to object to the officer because at the time he was using both his speedometer and his GPS to keep his speed under 50 kilometres an hour over the speed limit. He said his GPS showed 124 or 125 kilometres an hour. He said he knew he was speeding but that he was watching to make sure he didn’t go over 50 kilometres an hour over the speed limit because he knew the penalties were much higher for that

Reliability of evidence to the contrary:

In addition the speedometer and the GPS unit he was relying on to track his speed have not been established as accurate by any testing.

DECISION:

Mr. Anghel gave evidence that he believed he was travelling at a speed of perhaps 127 kilometres an hour. He based that belief on his speedometer reading and also his GPS unit. He acknowledged that he did not know if the GPS unit was capable of giving an accurate speed measurement, he did not give any evidence of having his speedometer checked for accuracy.

I am not satisfied that any defence to this charge has been made out and there will be a conviction for the offence of stunt driving, contrary to section 172(1) of the Highway Traffic Act.​

In most cases drivers are already going well over the limit anyway, so if you're arguing that your GPS/speedometer said 70km/h in a 60km/h zone rather than 75km/h in a 60km/h zone... the courts would happily accept your number and register a conviction.
 
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iFly55 said:
In most cases drivers are already going well over the limit anyway, so if you're arguing that your GPS/speedometer said 70km/h in a 60km/h zone rather than 75km/h in a 60km/h zone... the courts would happily accept your number and register a conviction.
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When I was charged for going 120 km/h a few years ago I brought a 1 second interval trail log, documentation on my gps accuracy, a map with my route and speed overlayed, and a comparison run with my gps and two others side by side to prove it was accurate. My top speed was 102KM/h in my log. They accepted my data and convicted me of going 102KM/h.

On the bright side, if I were accused of going over 50KM/h I guess my data would have saved me.
 
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In retrospective my mistake was that I showed my log from hwy exit to hwy exit. I was paced so I did not know at what point the officer obtained my speed. Next time I could ask for much more detailed points and trim my log to that exact spot, where hopefully I am under the limit.
 
In the quoted case the defendant stated his belief, based on what he saw on his GPS and speedometer at the time. This creates an additional level of removal from actual evidence making it the word of the defendant, based on uncalibrated equipment against the word of the officer, who is using calibrated equipment. When draught presented his GPS log as evidence it removed that barrier. He then took the extra effort to demonstrate some level of accuracy for the device.

In a case where speed is determined by pacing, asking that the court accept the word of the officer, a GPS record can be used to introduce reasonable doubt. The Crown has to prove guilt.
 
Interesting article of how GPS speed maybe more accurate than your speedometer. Anyone on the board know where to get calibration certificate for your speedometer? Do you basically get it checked by a mechanic, and have them write it's in working order?

Are there any speed data loggers that you can extract information from your vehicle's speedometer to present in court? I've read in some cases where newer vehicles have Collision Data Recorders.

Can we extract this data following a speed enforcement stop?

R. v. Cianchino, 2010 ONCJ 298 (CanLII)

Five seconds before the collision and just before he attempted to take the exit ramp to go south onto Highway 427, Micelli had been driving at a rate of speed that exceeded the posted speed limit by 19 k.p.h. This information about its speed was retrieved from the pickup truck’s Collision Data Recorder (CDR), which can record driver inputs, the speed of the vehicle, and the deployment or near deployment of airbags, for a five-second period before the collision. The CDR device recorded the pickup truck had been traveling at a speed of 119 k.p.h. five seconds before the collision occurred with the rear of the defendant’s vehicle and at one second before the impact the pickup truck had been travelling slower at 112 k.p.h.​

http://www.theglobeandmail.com/glob...driving-as-fast-as-you-think/article11487709/

Transport Canada says there are no federal regulations in North America regarding the accuracy of speedometers. Because speedometers and odometers are calibrated to the diameter of the original tires, Transport Canada spokesperson Maryse Durette says, “if the owner departs significantly from the manufacturer's original specifications at the time of purchasing replacement tires, the speedometer will no longer be in calibration.”​


http://www.theglobeandmail.com/glob...te-the-cars-speedo-or-the-gps/article4348596/

Take your car to a mechanic to ensure there are no issues with your speedometer. Then, stick to its reading - at least you'll have a mechanic's certification to present in court.​


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I loaded up Waze and a Garmin GPS while driving today and there was a huge discrepancy between my speedometer and the GPS speeds. 140km/h on the Speedometer was only 125km/h on the GPS. At lower speeds the offset was 5km/h.

This is just psychologically butt ****ing me, when I drive at the limit... I do feel that I'm a lot slower than surrounding traffic. If my actual speed is -15km/h below the limit, then I've been completely wasting my time and energy.

I've always felt comfortable doing 140 indicated but the fear of getting a +40km/h ticket or accidentally going into stunt tow always kept me well below. I guess I should continue driving at speeds I'm comfortable with, because they're consistent with the speed limit + enforcement buffer.

I'd much rather have a properly calibrated speedometer which shows my true speed, rather than having to guesstimate what speed I should be travelling.
 
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this is ******** though...how the hell can cops just pace you then and give you a ticket? I'm guessing their speedos aren't calibrated either. Pretty sure there was a guy here who got HTA 172 from being paced.
 
look inside a cop car they have a little sticker that say certified speedometer, it is part of the police package.
 
When I was patrol officer all our vehicles went in every three months to be calibrated by the mechanics for just this reason. The crown could show the calibration certificate, should it be challenged in court. Most of the officers knew of this but never actually saw the certificates. They were collected from the mechanic by the court liaison officer who then took them to the crown.
 
It's not true that there are "no regulations" for speedometer accuracy. Somewhere buried in CMVSS (which is the body of standards that the vehicle's original manufacturer has to build the vehicle in accordance with) are the requirements for how accurate the speedometer has to be. Basically, over a certain range of speeds which cover the entire "normal" range of posted speed limits and then some, the speedometer (1) can never read less than the actual road speed, and (2) it has to be within a certain percentage or a certain amount (it's complicated), and this has to be true for all tire sizes that are allowed (which pretty much means whatever tire size is printed on the vehicle's conformance label). What it amounts to is that every production vehicle has a speedometer that reads somewhere between dead-nuts accurate and about 10% higher than the real speed.

Your vehicle - if it's built since 1996 - internally knows what the real speed is, with the assumption that you are using the specified tire size. If you have an OBDII reader, you can read what it thinks the real speed is. If you have non-standard tires or tires with significant wear, it will still be off by a little.

My van reads very close (within 1 or 2 km/h), my ZX10R stock read 7% high but I have used a "speedo-healer" to get it right, my car reads 10% high on the speedometer but OBDII is very close to what a GPS says.
 
Brian P said:
My van reads very close (within 1 or 2 km/h), my ZX10R stock read 7% high but I have used a "speedo-healer" to get it right, my car reads 10% high on the speedometer but OBDII is very close to what a GPS says.
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Why would the speedometer read different than the OBDII? I noticed this on my last car
 
CruisnGrrl said:
Why would the speedometer read different than the OBDII? I noticed this on my last car
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Because the speedometer can never read low (so the manufacturers make it read high). OBDII shows the base data (probably the same data that increments the odometer). One of the manufacturers got in trouble a few years ago (Honda?) because they messed up and had the odometers counting too fast (shortening warranty periods and accelerating depreciation).
 
with the deep treaded tires on the work truck i'm always reading higher than gps on the vehicle.
 
CruisnGrrl said:
Yes but why is intentionally higher instead of the same?
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Because if it's going to be out of spec it's better that it read high, than low. There's no liability if it registers low. If speedos were to register high, then everyone and his cousin would sue the auto manufacturer every time they got a ticket.
 
CruisnGrrl said:
Yes but why is intentionally higher instead of the same?
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from http://www.theglobeandmail.com/glob...driving-as-fast-as-you-think/article11487709/

The difference between actual speed and the speed dial tends to get noticed more with German cars because their speedometers are designed to never report a speed lower than actual speed. European law (ECE-R39) says speedometers cannot show speeds less than the actual speed, and they must never show more than the 110 per cent of actual speed plus 4 km/h. So, under those rules, a car could be moving at 100 km/h, but the speedometer could legally display as high as 114 km/h.
 
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