NY Times 
July 31, 2013
In a significant victory for law enforcement, a federal appeals court on Tuesday said that government authorities could extract historical location data directly from telecommunications carriers without a search warrant.
The closely watched case, in the United States Court of Appeals for the Fifth Circuit, is the first ruling that squarely addresses the constitutionality of warrantless searches of historical location data stored by cellphone service providers. Ruling 2 to 1, the court said a warrantless search was “not per se unconstitutional” because location data was “clearly a business record” and therefore not protected by the Fourth Amendment.
The ruling is likely to intensify legislative efforts, already bubbling in Congress and in the states , to consider measures to require warrants based on probable cause to obtain cellphone location data.
The appeals court ruling sharply contrasts with a New Jersey State Supreme Court opinion  in mid-July that said the police required a warrant to track a suspect’s whereabouts in real time. That decision relied on the New Jersey Constitution, whereas the ruling Tuesday in the Fifth Circuit was made on the basis of the federal Constitution.