While the Senate's ECPA Amendments Act doesn't deal with geolocation information, a bill called the Geolocational Privacy and Surveillance (GPS) Act, with versions introduced both in the House and the Senate, would require warrants for that information.
The American Civil Liberties Union supports the GPS Act, said Catherine Crump, a staff attorney for the group.
"Mobile phone technology provides law enforcement agents with an invasive yet inexpensive method of tracking individuals over extended periods of time and unlimited expanses of space as they traverse public and private areas," she told the House subcommittee. "It also makes it possible for law enforcement agents to identify all individuals located in a specific area -- a valuable tool, but one that by necessity reveals the location of vast numbers of innocent Americans."
But the bill would make it more difficult for law enforcement agencies to obtain geolocation information, thus hindering investigations, said Peter Modafferi, chief of detectives, in the Rockland County, New York, District Attorneys Office. Nearly every crime now has digital evidence associated with it, he said.
"Utilizing this [geolocation] information in the early stages of an investigation often provides fundamental building blocks on which cases may rest," Modafferi said. "Requiring probable cause in the initial stage of an investigation to gain access to geolocation information would make it significantly more difficult to solve crimes."
Grant Gross covers technology and telecom policy in the U.S. government for The IDG News Service. Follow Grant on Twitter at GrantGross. Grant's e-mail address is firstname.lastname@example.org.