(arstechnica)
In a 2-1 ruling, the US Circuit Court of Appeals for the Sixth Circuit has ruled (PDF) that law enforcement has the right to obtain location data from a cellphone in order to track a suspect without a warrant. The case involves a man named Melvin Skinner, a newly convicted drug trafficker, who was part of a cross-country, large-scale drug operation organized by another man, James Michael West.

Skinner had appealed his many convictions: conspiracy to distribute and possession with intent to distribute over 1,000 kilograms of marijuana, conspiracy to commit money laundering, aiding and abetting the attempt to distribute in excess of 100 kilograms of marijuana. His attorneys argued that the government’s use of his GPS location information from his phone, which led to his arrest, constituted a warrantless search in violation of the Fourth Amendment.

"There is no Fourth Amendment violation because Skinner did not have a reasonable expectation of privacy in the data given off by his voluntarily procured pay-as-you-go cell phone," wrote Judge John Rogers, in the majority opinion. "If a tool used to transport contraband gives off a signal that can be tracked for location, certainly the police can track the signal..."
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