A federal court has ruled that warrantless cell phone tracking by police is legal.

The U.S. Court of Appeals for the Sixth Circuit yesterday ruled (PDF) that law enforcement officials were within their legal right to track Melvin Skinner, an alleged drug trafficker, through his cell phone before his arrest in 2006. According to court documents, law enforcement officials were able to use the GPS feature on Skinner's cell phone to track his whereabouts and eventually arrest him.