The U.S. Supreme Court opened its 2011 Term this week, and one of the cases on the docket is one of the most significant Fourth Amendment cases in years.  United States v. Jones, involves the use of GPS devices to track a person's movements, 24 hours a day, for days or weeks at a time.  That information can then be analyzed by sophisticated computer software to show patterns of movement and private association.  The potential for abuse is overwhelming, which is one of the reasons why the Court of Appeal found that the Constitution provides protection against the use of such devices.  Here in Maine, we have been engaged in an investigation of how and when law enforcement agencies use the GPS chips in our cell phones to track our movements.  So far, we have found that very few departments have comprehensive policies in place to protect the privacy rights of individuals.  Our investigation, and advocacy, continues.  In case you are interested, here is the ACLU's amicus curiae brief in the Jones case.