By James Q. Lynch

Ruling in the case of an Eastern Iowa teenager who killed his grandparents, the Iowa Supreme Court has concluded that sentencing a juvenile offender to life without the possibility of parole violates the state constitution.

The ruling comes in the case of Isaiah Sweet, then 17, of Manchester who pleaded guilty to killing his grandparents, Richard Sweet, 55, and Janet Sweet, 63, in 2012.

Sweet said in court he intended to murder them "before, during and after" he shot them in the head with a high-powered rifle in their Manchester home. He acknowledged the state could prove that he did so "willfully, deliberately and premeditatively."

A district court judge called two sentences of life without parole appropriate for Sweet because he was a coldblooded murderer who had little chance of rehabilitation.

However, in concurring with the 4-3 majority, Chief Justice Mark Cady said sentencing a teenager to life without parole violates the Constitution's cruel and unusual punishment clause.

Judges cannot predict whether a teen murderer might be rehabilitated in the future, Cady said. There is an "inherent deficiency" in the information available that makes it "cruel to sentence a youthful offender to life without the possibility of parole at a time when the juvenile has not even had the time to finish maturing."

"In particular, a juvenile offender who is resentenced based on evidence of rehabilitation acquired after full brain development has occurred may present a far better case for parole than an offender who has not completed brain development," he wrote.

In a dissenting opinion, Justice Edward Mansfield said the majority lacked justification to break new ground by categorically forbidding life without parole sentences for teen felons.

"More is needed before we strike down a legislatively authorized sentence -- especially one the General Assembly reauthorized by large majorities in both (chambers) just last year," Mansfield wrote.

(c)2016 The Gazette (Cedar Rapids, Iowa)