Peterson Defense Objects to GPS Evidence
Defense to Argue That GPS Technology That Tracked Scott Peterson Is Inaccurate and Unreliable

The Associated Press

REDWOOD CITY, Calif. Feb. 11 — Defense lawyer Mark Geragos will try to convince the judge in the Scott Peterson double-murder case Wednesday that global positioning technology is inaccurate and unreliable.

Legal experts said he faces an uphill battle, since the technology has been in use for many years by airline pilots and even hikers to pinpoint locations to within a few feet, using signals bounced off satellites.

Geragos has said his client was tracked by Global Positioning System devices placed by authorities in vehicles he drove after his wife, Laci, disappeared on Christmas Eve in 2002. Geragos wants all the GPS tracking evidence excluded from the trial.

"The GPS technology has not been generally accepted by the scientific community," he contended in court papers filed in October.

Geragos faces a gag order and can't comment on what he hopes to gain by keeping the tracking evidence out of the trial. Likewise, prosecutors haven't said how they hope to use the evidence.

If his claims about GPS unreliability fail to persuade Judge Alfred A. Delucchi at the Wednesday hearing, Geragos hopes to prove the device used to track Peterson was operated improperly by Modesto police.

Police used GPS to track Peterson from Jan. 3 through April 22, 2003, when they arrested him near San Diego only days after the bodies of his wife and unborn son surfaced in San Francisco Bay.

GPS was first developed for military use in 1978. In California, prosecutors who use GPS evidence in court are required to establish the device's reliability using properly qualified experts.

Prosecutors not connected to the Peterson trial say this shouldn't pose a problem.

"We all know from how much we use GPS now that it's quite accurate," said Mark Hutchins, senior deputy district attorney in Alameda County. "Airplanes use it. Everyone's got a GPS map thing in their car."

Although to me this one is a no-brainer.....everyone knows how accurate GPS technology is. My boss used to be in the US Forest Service- he used it all the time and he said it's almost frighteningly accurate. We were talking about that movie "Enemy of the State" where they use GPS to track Will Smith's character. My boss said that although it was somewhat exaggerated for the movie, the technology is available to use in just that way, and it's incredibly accurate.

I'm pretty sure that LE has much better equipment than my $299 unit.

Unless the unit that they used was very old, and they didn't know how to set it up, I see no reason why the information wouldn't be accurate.

I personally lean toward tossing it out. I have a couple of reasons, first, it did malfunction, they have admitted that much. I don't know if it had "blackouts" or transmitted bad data or how bad the data was, and I'm not sure if they can prove if the data was bad or not. Scott surely is not going to admit to being anywhere at this point.

Second, GPS cannot tell WHO was driving the vehicle. Just because the vehicle was somewhere, doesn't necessarily mean Scott was the driver. GPS cannot tell the reason for the vehicle being at a location. It would be strictly speculation to say that because the vehicle was somewhere, (let's say at the bay) that Scott was the driver, and the reason was to "return to the scene".

I hope there was a warrant, because if not, I don't think that there will be any question here....

Regarding if I think it should be allowed or not, Well, if they had permission to do it, then yes.

Let the jury determine if the information is reliable or not.

It seems that GPS is being used a lot with murder suspects...

By following the GPS lead LE discovered the location. LE found a shallow empty gravesite. It wasn't long before GPS tracked Brad Jackson's movement to the second shallow gravesite where his daughter's body was found. This site was some miles away from the original burial site. In that situation GPS tracking was successful. Incidentally, Brad Jackson had also taken part in search efforts. Valerie's Mother had vanished several years before. Last report I have had, she has not been found.

As for following Scott Peterson unknowingly GPS tracking was planted in his vehicles or rented vehicles and had malfunctioning equipment. Malfunction was at least four times is reason the judge tossed GPS tracking out of this trial. I have no known reason to believe judge would not have allowed if the equipment was functioning properly.

As for testimony from those that 'followed' Scott, are you suggesting that records of paperwork of GPS 'followed by electronic equipment'? It would be 'hearsay' testimony toss out, same as gossip or a letter sent to the court, IMO.

REDWOOD CITY - Evidence from satellite tracking devices covertly placed on
Scott Peterson's vehicles will be allowed at his trial on double murder
charges, but prosecutors will have to tell the defense where police placed
the units, a judge ruled today.

http://www.modbee.com/reports/peterson/trialupdates/

http://www.modbee.com/reports/peterson/trialupdates/
...................................
Hearsay allowed...
EDITED : Ooops ! same report as above

The GPS technology is relied on in war and peace for a variety of extremely critical operations. A supertanker has a GPS in its bow and stern to compute the precise location of each of those points.

Sure, devices when started often capture incomplete data and adjust their results as they capture more satelite signals. There is also telemetry problems and electronic interference problems such as from ignition sources, etc.

The information is reliable. Even an inertial guidance system that steers your airliner through the sky reads the wrong course for 98 percent of the flight!

As to hypnosis: this is often considered spoliation of evidence. A witness is supposed to appear before the jury and give their testimony not someone else's testimony. Hypnosis is a highly suggestible state and subtle questioning techniques can induce a belief in a desired response. Any fact that is suggested can lead to confabulation, the invention of reasonable facts to support a suggested fact. (Example: tell someone they ate dinner last night at an Italian restaurant and then much later ask them what they had for dinner last night. Even though there was no direct suggestion of what their entree was, they will indeed supply a reasonable answer to conform to the suggested fact of having dined in an Italian restaurant.)

Videotaping of such sessions is the normal procedure and defense presence if possible. A witness should be carefully examined prior to any hypnosis and the testimony preserved.