A US Court of Appeals for the Sixth Circuit yesterday found that police were legally allowed to track a particular man through his cellphone. The man. Melvin Skinner, was caught and arrested for selling drugs in 2006. The only reason the police found him at all is because they tracked the GPS feature on his cell phone and were able to pinpoint his location to arrest him.

“The drug runners in this case used pay-as-you-go (and thus presumably more difficult to trace) cell phones to communicate during the cross-country shipment of drugs. Unfortunately for the drug runners, the phones were trackable in a way they may not have suspected. The Constitution, however, does not protect their erroneous expectations regarding the undetectability of their modern tools,” says Judge Rogers, one of the judges that ruled in favor of calling the tracking legal.

However, the US Supreme Court has had several of these cases over the years and has always ruled unanimously that police must obtain a warrant before tracking smartphones through their GPS function. The judges say that in this particular case, the phone did not require any physical interaction to track and thus did not require a warrant.

“When criminals use modern technological devices to carry out criminal acts and to reduce the possibility of detection, they can hardly complain when the police take advantage of the inherent characteristics of those very devices to catch them,” Judge Rogers stated. “This is not a case in which the government secretly placed a tracking device in someone’s car.”

Several companies and organizations are arguing against the ruling such as the American Civil Liberties Union and the Center for Democracy and Technology. Both say that a warrant should be required for tracking any GPS, regardless of physical interaction or not, due to the Fourth Amendment. Though one of the judges on the three judge board agreed with these organizations, the other two did not, and the ruling was made.