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GPS Tracking Device Beats Radar Gun in Court
MojoKid writes "According to a release issued by Rocky Mountain Tracking, an 18-year old man, Shaun Malone, was able to
successfully contest a speeding ticket in court using the data from a GPS device installed in his car. This wasn't just any old make-a-left-turn-100-feet-ahead-onto-Maple-Street GPS; this was a vehicle-tracking GPS device — the kind used by trucking fleets — or in this case, overprotective parents. The device was installed in Malone's car by his parents, and the press release makes no mention if the teenager knew that the device was installed in his vehicle at the time."
If only.
GPS device gets time from GPS satellite, not user.
Come to think of it, that's a great idea for OS or FSF - create code for popular GPS devices, and then produce the code for audit when you go to court contesting a ticket, while asking that the cops produce the code off of their device!!
A variation of this has been done in a number of DUI/DWI cases. A number of defendants have demanded that the source for the breathalyzer be made available for review by the defense.
In the cases I'm aware of, the manufacturer has refused to release the source as their agreement/license with the relevant law enforcement agency does not provide for this.
I believe the outcomes have ranged, but in general this has been a successful defense.
I'm no fan of the cops, but measuring at an angle to the direction of travel decreases the speed as perceived by the radar gun.
If your GPS time was off by even one second, your position would be off by about 300km -- give or take depending on satellite geometry -- there's no way to separate the two.
Sure there is. The GPS clock system is independent of our common business-day clock. GPS does not incorporate time zones, does not incorporate daylight savings time adjustments, does not incorporate leap years or leap days or leap seconds or anything else. It is not tied to any earth time system. The GPS network simply counts its own seconds, independent of our earthly wall-clock time conventions.
The GPS unit likely has an independent clock circuit so that you can have a clock even when you are not receiving any GPS signals. And if it is running off of satellite time, it would have to have some stored translation factor to convert the satellite time to an earth-clock time, to account for time zones and daylight savings time and other adjustments, and to account for the fact that the satellite time *does* drift out of sync with official earth time systems. In fact due to leap seconds and whatnot, GPS time has drifted 14 seconds out of sync with GMT / UTC Coordinated Universal Time.
The fact that it was even physically possible for him to manually set the clock proves that the satellite time was not being directly displayed on the clock, that there is either an independent internal clock and/or some stored translation factor to convert the GPS network's internal clock system into whatever "common local time" you want displayed on the user-clock. None of this would would be used in the GPS position calculations.
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- - You can't take something off the Internet! That's like trying to take pee out of a swimming pool.
A series of lights.
As in, more than one light, and based on which ones were lit, the driver's speed is indicated.
For example:
1 light = 10 mph.
2 lights = 30 mph
8 lights = 100mph
If that still doesn't make sense, then you're just too retarded to understand.