Who killed Teresa Halbach? Steven Avery's attorney says new evidence uncovered shows it was someone other than her client.  

Kathleen Zellner filed paperwork this week implicating Avery's nephew, Bobby Dassey and Dassey's stepfather in the murder. It also claims people knew Halbach left Avery's property before she disappeared. 

Zellner made the filing in another attempt to seek a new trial for Avery. A judge said no to a recent request.