gps speeds

As far as I recall, the car speedo can overstate the actual speed but not understate it. I'd be checking yours out with another GPS to be sure, to be sure :)))

T-Ribby,

That would be pretty normal.

In 2005 Jerry Si****s successfully challenged a $160 speeding fine, proving in court that the hand-held radar gun that was said to show he was travelling at 133 kmh in a rented Pulsar had never been properly calibrated, tested or maintained.

Last week his son Michael, 25, went one better; overturning a speeding conviction and fine by downloading the information from his car's GPS unit to show that he was travelling at or below the speed limit and not at 85 kmh in a 60 kmh zone as alleged by two police officers, who admitted in court they had incorrectly used a hand-held radar unit.

The experience has cost the family more than $27,000 in fees for lawyers and experts, but justice, they said, had been worth the money and created a legal precedent that their lawyers said could spark more regular challenges to technology that experts say is questionable and prone to inaccuracy.

Jerry Si****s was driving from Melbourne in May 2004 when he was clocked by police on the Hume Highway at Jugiong, 40 kilometres north of Gundagai, allegedly doing 133 kmh in a 110 kmh zone.

He challenged the fine in court, questioning how rigorously police recalibrated their radar guns for accuracy each year and presenting documents in court, which showed police certified the US-made Kustom Silver Eagle gun as accurate even though half of the possible 18 tests - which cover issues such as temperature, vibration stability, noise and phone interference, and humidity - were never done.

After three days in court, in which two experts in radar gun technology gave evidence, the police gave up. It cost Jerry Si****s $20,000 in legal fees.

Michael Si****s was charged a few weeks after his father - his first speeding fine - while driving his Subaru WRX home just before midnight along Marsden Road in Carlingford. He was stopped and charged by two patrol officers driving in the opposite direction.

The officers had clocked him with a hand-held radar allegedly doing 85 kmh in a 60 kmh zone, but conceded in court they had not taken the reading for the required length of time. Instead they relied on their own experience and visual estimate.

The evidence Michael Si****s presented that was downloaded from his GPS unit showed that between Eastwood and Carlingford the car once briefly touched 61 kmh but was mostly at 57 kmh. An expert in GPS systems provided corroborative evidence in court.

Despite this, the magistrate convicted him on the evidence of the visual estimate of the most senior officer and fined Mr Si****s $203. Last week the conviction and fine were overturned on appeal in the District Court after the police again backed down.

Jerry Si****s said he was concerned about the police's use of radar equipment. "The message is that police have an obligation to use this equipment properly. Motorists have the right to expect that they prove it is accurate."

Michael Si****s's lawyer, Dennis Miralis, went further. The first case in NSW where GPS has been admissible in evidence to contest the accuracy of police radar would not be the last, he said.

"There is an enormous amount of conservatism in the legal fraternity about acceptance of new technology. Magistrates seem to prefer to accept whatever police say in defence of their own equipment, but there are growing doubts."

Radar and laser devices are calibrated every year but GPS aren't so you have to prove that the GPS was calibrated in court. The police backed down on the speeding fine when they shouldn't have.

I met a bloke who makes a living as expert witness in radar cases. It can be done but it costs. You would think case law would have put an end to speeding fines by now. If they did it would be back to heaps of cops on bikes which I reckon is better anyway cos they could be stopping all those hoons that freqyent the roads these days. I got no beef with radars but then I drive defensively anyway and seldom get sprung speeding.

Owen

Had a few speeding tickets over the years, but cant say any of them were undeserved. I havent ever been accused by a cop of speeding when I havent. And a few have let me off as well. I reckon that they do a pretty tough job and face some pretty bad sh+t. Sometimes Id argue the point but I wouldnt spend $27000 to defend it. Some cops are ar.eholes without a doubt but maybe some dont cope so well with the daily stream of crap put in front of them. It would be very tempting to stretch the facts when confronted with some smart alec P-plate kid who you know you will have to hose off a power pole sometime in the future.

Well my Garmin GPSMap60C manual claims:

"GPS Accuracy = 0.05 meter/sec steady state".

A quick calculation = 0.18 km/h.

Good enough for me!

Neville

The Police may have dropped the case due to them not actualy having "the facts". They admitted that they 'estimated' some of their evidence. On the basis of the reports that we read in this thread I doubt that there actually was a case in the first place as court evidence must (or should) be based on 'facts' and not some guys estimation of speed. I don't actually see any precedent other then showing that the Police were careless in the use and operation of their equipment.

You need to remember that with any allegaton it must be supported by evidence that can be substabtiated.

Police give evidence as to date, time, location, speed as indicated on their measuring/timing device or in some cases observations.

Accused attendeds court, listens to allegation(s), as does Magistrate, accused or their representative responds to allegations and in some cases may introduce evidence to rebutt Prosecution's claims. The rebuttal may be in the form of evidence to the contrary, that cannot be refuted by Police, (e.g. track readout from a GPS), evidence or doubt that Police may have not been operating within guidelines as specified by the equipment manufacturer or even thier own Operational Orders (yes there are such orders and they can be very specific. Failure of Police to comply may constitute a breach of their Code of Conudct etc).
If the Magistrate accepts such arguements then he is compelled to make judgement accordingly. That is, if there is any doubt as to the accuracy, truthfullness or credibility in what has been alleged - by Police, then the charge(s) should/must be dismissed.
Remember - for the proof of law, the evidence (by Prosecution) must be Beyond Reasonable Doubt. If you or your Counsel can introduce a Reasonable Doubt then you have won the day.
Best advise - DON'T SPEED.

GPS speeds are very accurate and can be used to check your speedo and odometer for accuracy but do not depend on them in court as it is entirely up to the magistrate at the moment weather he believes your unit or not.
I use both of mine a navigator type and a true GPS type and I find that for speed and distance they are always the same. And I know that my speedo is in error because of larger tyres.

Well we in Vic have to estimate the speed before we use the laser and when you have been doing this for over 18 years, you get pretty damn good. Only legislation states that the laser/radar must be fixed for a certain time but when I point the radar out the car when I am driving my speedo is pretty much spot on with the radar. I would have sent the 200 dollars on the speeding fine not $27,000 that's just stupid. If I get a ticket I just pay it as one person said earlier in the thread it's a s...t of a job!!!!!!!!!!!!!!! Someone has to do it.......................

fm
P.S. Crap is not the word for it, that's understating.

Tx all. I enjoyed the theoretical dissertations. I thought the advice to cross check witha another GPS good sense so I took my old Lowrance out and ran it against the newer Garmin. the results were that the Lowrance moved around a lot more (ie was more fluctuating or sensitive) but when I settled to a cruise so did the 2 GPS units, plus or minus 0.5. So the Mits Speedo is too slow by about 7 kilometres per hour. Allowing for the 2-3 kph that we all sneak over the limit, that's nearly 10 kph I could have lost on the last trip. As it was 4000 K'S, that's a lot of extra driving time (tried to calculate it but I'm either too tired or stupid, probably both).