(St. Paul, MN)  --  Charges against the man accused of shooting Mahnomen County Deputy Chris Dewey have now been elevated to second-degree murder.  Minnesota Attorney General Lori Swanson has filed amended charges against 33-year-old Thomas Fairbanks of Anoka, who was originally charged with attempted murder.  Deputy Dewey died Monday morning, nearly a year-and-a-half after he was shot.  Under Minnesota law, intentionally killing an on-duty police officer carries a charge of first-degree murder, but only a grand jury can make that charge.  It's expected a grand jury will be called but there's no word yet from Mahnomen County prosecutors.