Chief Justice Roberts has ordered the Marshal of the Supreme Court (a retired Army Colonel) to conduct the investigation into last week's leak from the Court.  This would be a difficult assignment for seasoned FBI agents who specialize in these types of investigations,  but it is particularly daunting for the Supreme Court Marshals whose primary function is to provide security for the Justices and the Supreme Court building.  ABC News's crime & terrorism analyst Brad Garrett discusses the challenges of the investigation.