Prosecutors in the murder trial of Scott Peterson are attempting to be the first in the state to have evidence produced by a vehicle's global positioning system admitted at a criminal trial.
Stanislaus County Deputy District Attorney Rick Distaso and defense attorney Mark Geragos spent most of today questioning GPS expert Peter Loomis about the technology, which was used in a tracking device that police concealed on Peterson's vehicles after his pregnant wife Laci disappeared on Christmas Eve 2002.
Geragos contends that the GPS evidence should not be admitted at the trial because it is inaccurate, largely because the device's antennae were hidden underneath the vehicles and could not get an accurate fix on the satellites that are the heart of the GPS system.