FEBRUARY 19, 2014
Yesterday, in a 5-2 decision, the Massachusetts Supreme Judicial Court (SJC) ruled that state law enforcement may not compel cellular telephone service providers to provide historical cell site location information for a particular cell phone without first obtaining a valid search warrant. In other words, under Article 14 of the Massachusetts Declaration of Rights, the government may not use a person’s cell phone records to track that person’s physical location unless they have first obtained a search warrant supported by probable cause.
Cell phone service providers use cell sites or cell towers placed throughout particular regions, which send and receive signals from a subscriber’s cell phone that is operated within the particular region. When a subscriber makes or receives a call, a record is created of the cell site used. This information enables a cell phone service provider to approximate the location of an operating cell phone within its network based on the cell phone’s communication with cell sites in the area. The greater number of cell sites in a region, the greater the accuracy of the cell phone’s location.