It seems as though there may just be a positive side to those unwelcome GPS-based vehicle tracking devices... especially if you are a teenager. Shaun Malone, a 17-year-old California resident, was cited by radar-yielding authorities for driving 62 mph in a 45 mph zone in 2007. Faced with a $194 fine (and some inflating insurance premiums), Shaun's parents fought back arguing their son's vehicle was equipped with a satellite-based tracking device that monitored Shaun's speed – and it showed he was doing 45 mph when he was stopped.

While they can be affected by poor reception or noise in the radio signal, GPS-based speedometers are generally considered the benchmark for measuring velocity. On the other hand, radar measurements are also considered very accurate, as long as the human at the other end of the device is correctly trained and is tracking the proper vehicle. At stake is the credibility of radar. As Doppler-based speed enforcement has become a primary source of revenue for law enforcement agencies nationwide, police don't want their technology challenged. With that in mind, the local Petaluma police have spent a reported $15,000 on the trial. The case is to be decided in the coming weeks.

[Source: Christian Science Monitor]