 Hennepin County is launching a conviction integrity unit, which will review past legal cases for possible wrongful convictions. Hennepin County Attorney Mary Moriarty announced today that Attorney Andrew Marquardt will lead the office. Marquardt investigated wrongful convictions with the Great North Innocence Project. He recently represented Marvin Haynes, whose 2005 murder conviction was overturned last December. Marquardt says this will help more people like Haynes.