Ronnie Allen Rush will get a new trial involving the deaths of Warden Groves and Mary Hicks.
The State Supreme Court ruled the State Police improperly heard statements from the 16 year old.
They did rule that he will still be tried as an adult.
Rush said he asked and was allowed to leave, but a trooper intimidated him into staying.
A jury convicted Rush two years ago of voluntary manslaughter.
He was declared mentally impaired at the time of the murder.