By Richard Willing, USA TODAY
Just after Laci Peterson disappeared in Modesto, Calif., on Christmas Eve 2002, her husband, Scott, assured police that he had nothing to do with it.
But police were suspicious. Without Peterson’'s knowledge, they received court permission to attach global positioning system tracking devices to the undersides of three vehicles he was known to drive. The devices, which use cell phone networks and signals from orbiting satellites to pinpoint land locations, indicated that twice in January 2003, Peterson drove to a San Francisco Bay marina near where the bodies of his wife and unborn son washed ashore three months later.
Peterson, 31, now is on trial for murder. Prosecutors say they’'ll use the data gathered by the GPS devices as part of a body of evidence that suggests Peterson is guilty.
The use of GPS in the Peterson case reflects how police across the nation are turning to such devices for surveillance, eavesdropping and other tasks that traditionally have been performed by uniformed officers and detectives. Recent improvements in cell phone technology and in the quality of satellite signals allow officers to track and record a vehicle’'s movements in real time, on a map displayed on a laptop computer.
A typical GPS tracking device is about the size of a paperback book and can be affixed to a car’'s undercarriage with a magnet. Manufacturers say its cost — about $1,000 — is headed down as the market for the devices expands.
Questions over whether police need a court’'s permission to use GPS devices in investigations have set off legal battles in state and federal courts across the nation.
Wiretaps and property searches ordinarily must be authorized by a state or federal judge, who determines that such tactics are needed to investigate a crime. But surveillance on public roads ordinarily does not require such orders. Because a GPS device is a substitute for ordinary visual surveillance, some police departments believe that it can be used without their having to obtain a court order.
Such thinking suggests that “technology has gotten us to where police can track thousands of people anywhere, anytime (and) don’'t even have to give a reason,” says Bruce Barket, an attorney for a burglary suspect who was tracked by GPS in New York.
“The law needs to keep up with technology,” Barket says
Wide range of cases
There are no records of how often GPS is being used nationally, and by which departments. But court records and interviews with law enforcement officers and lawyers across the nation indicate that local authorities and the FBI have used GPS devices in a range of cases:
- In Honolulu last month, a police unit that fights auto theft parked a car with a GPS tracker in a high-crime area. The “bait” car was stolen and was located quickly. Police arrested the driver.
- Police in Nassau County, N.Y., used a GPS device to track a car driven by burglary suspect Richard Lacey in 2002. Police plan to use GPS records to show that the car was in the vicinity of several homes at the time they were burglarized. Barket, Lacey’'s attorney, has asked a judge to exclude the GPS evidence from trial.
- In Las Vegas in 2000, the FBI used a GPS device that had been built into a car to eavesdrop on the targets of an investigation into organized crime. The device, offered as a safety accessory by some carmakers, allows lost or endangered drivers to be located quickly if they call in for help. No arrests were recorded in the Nevada case.
- In Spokane, Wash., in 1999, GPS devices on a Ford pickup and a Honda Accord driven by murder suspect William Bradley Jackson led police to the grave of his missing 9-year-old daughter, Valiree. Jackson, the GPS data indicated, made two trips to the site in the three weeks after he reported the girl missing. He was convicted of murder and sentenced to 56 years in prison.
GPS devices were developed by the military in the 1980s. The devices read signals transmitted by a network of 24 satellites. A GPS device calculates its location based on its distance from each satellite. A built-in modem and antenna transmit the information like an ordinary cell phone call.
The system can be accurate, proponents say, down to a nanosecond and within 20 feet.
Police say GPS devices have distinct advantages over human trackers: They can operate around the clock without a break, and they’'re less likely to lose track of a target or be noticed. “The human element for error gets taken away,” says Sgt. John Urquhart, spokesman for the King County, Wash., sheriff’'s department.
Court rulings
Courts are just beginning to tackle issues raised by GPS use.
In the Jackson case in Washington state, police argued that the devices do not require a warrant because they provide the same information as a visual search. The state’'s court of appeals agreed, finding that the GPS devices used to track Jackson were “merely sense augmenting” and revealed information open to “public view” as Jackson traveled county roads.
But the state Supreme Court disagreed. Under Washington’'s constitution, the court said, GPS surveillance requires a warrant because it amounts to a search.
“The intrusion into private affairs made possible with a GPS device is quite extensive,” Justice Barbara Madsen wrote last September in an opinion joined by all nine of the court’'s justices. “Vehicles are used to take people to a vast number of places that can reveal preferences, alignments, associations, personal ails and foibles.” GPS, she said, “can provide a detailed picture of one’'s life.”
But the court upheld Jackson’'s murder conviction. Spokane County sheriff’'s deputies had taken the precaution of getting a warrant, even as they argued that it wasn’'t needed.
Legal analysts say federal courts might reach a different conclusion. A pair of 20-year-old U.S. Supreme Court cases permit police to plant electronic transmitters on vehicles without a warrant and to track them, as long as the vehicles do not enter private property.
Rob Cerullo, a Chesterfield County, Va., police officer and University of Richmond law student, says U.S. agents could argue that GPS devices are legally indistinguishable from such old-fashioned transmitters. Cerullo wrote an article on GPS law for the May 2004 issue of Police Chief magazine.
Besides tracking suspects, police departments also are using GPS devices to check on the activities of their own employees. In the past five years, departments in Des Moines, Omaha, Orlando and other cities have used GPS devices on police cars to track the cars’’ whereabouts during duty hours.
In Clinton Township, N.J., in 2001, five officers were let go after their handwritten activity logs conflicted with information collected by GPS devices.
One night-shift officer reported that he had spent about two hours checking the security of a residence and several local businesses. The global-positioning data indicated that his cruiser had been parked at a McDonald’'s restaurant all that time.