(CNN) -- A three-judge panel has reversed a lower court's ruling to try a 12-year-old murder suspect as an adult.
In a 2-1 decision, the Superior Court of Pennsylvania vacated the trial court's refusal to transfer the case to juvenile court and sent the case back for a new hearing.
In a written opinion, the court said it "contends that the trial court committed an error of law in applying a provision of the decertification statute in a manner that infringed upon his Fifth Amendment rights against self-incrimination."
Lawrence County Judge Dominick Motto had refused a request to send the case to juvenile court because the youth refused to accept responsibility or admit guilt, and therefore deemed him a poor candidate for rehabilitation -- something that is considered vital for approval to send serious cases to juvenile court.
The youth has consistently asserted that he is innocent of the February 2009 killing of his father's pregnant girlfriend.
"He was penalized for exercising his constitutional right against self-incrimination by being required to say he is remorseful and accept responsibility for something he claims he did not do, " said the youth's attorney, Lourdes Rosado of the Juvenile Law Center, who argued the case before the Superior Court panel in January.
"The majority correctly recognized that the trial court had placed an unconstitutional condition on (the youth) in his effort to be tried as a juvenile," she said.
"We're reviewing the details in the ruling," said Nils Frederiksen, spokesman for the Pennsylvania attorney general's office, "and we will proceed in a manner that we feel is appropriate. The burden of proof remains on the defendant to transfer the case to juvenile court."
The 26-year-old victim was eight months pregnant when she was murdered, and the child was also killed.
The suspect was 11 years old at the time of the deaths.
Police say the victim was shot once at point-blank range in her farmhouse in western Pennsylvania.
The youth, who was living with his father at the time, was charged with one count each of criminal homicide and homicide of an unborn child.
The weapon was a youth model 20-gauge shotgun, designed for use by children, that belonged to the boy, according to investigators.
The case now goes back to the lower court, the Lawrence County Court of Common Pleas, in front of the same judge, Dominick Motto. The hearing to determine whether he'll be transferred to juvenile has yet to be scheduled.