GPS technology finding its way into court

The rapid spread of cellphones with GPS technology has allowed police to track suspects with unprecedented precision — even as they commit crimes. But the legal fight is only now heating up, with prosecutors and privacy activists sparring over rules governing the use of powerful new investigative tools.

The US Court of Appeals for the 6th Circuit stirred the debate last week when it supported police use of a drug runner’s cellphone signals to locate him — and more than 1,000 pounds of marijuana — at a Texas rest stop. The court decided that the suspect “did not have a reasonable expectation of privacy” over location data from his cellphone and that police were free to collect it over several days, even without a search warrant. The decision riled civil libertarians, who warned that it opened the door to an extensive new form of government surveillance destined to be abused as sophisticated tracking technology becomes more widely available. On August 20, six days after the appeals court ruling, the U.S. attorney in Arizona cited it in defending the use of cellphone location data to help arrest a suspect accused of tax fraud. “We’re looking at the very frightening prospect of an excessive degree of government intrusiveness in our personal lives,” said Gerald L. Gulley Jr., the Knoxville, Tenn., lawyer who represented the drug-running suspect at the Texas rest stop. “I don’t think that people who go out and buy cellphones necessarily contemplated . . . the degree of intrusion in their personal life.” Gulley says he’ll appeal the case.