WGBH's Morning Edition host Joe Mathieu spoke with WGBH legal analyst and Northeastern law professor Daniel Medwed about Victor Rosario, a Lowell man who spent 32 years in prison for an arson that caused eight deaths, including five children. In May, the Supreme Judicial Court upheld a lower court decision that granted him a new trial, and last Friday the Middlesex County District Attorney’s Office announced that it does not intend to retry him.  The parties are scheduled to appear in court tomorrow to formalize that decision.