In 2005, Mr. Jones was convicted of murder and sentenced to life without the possibility of parole, which was then the mandatory penalty under state law.
David M. Shapiro, a lawyer for Mr. Jones, said his client “committed a murder for the most immature reason possible — teenage infatuation.” In the years that followed, Mr. Shapiro said, Mr. Jones has proved that he is not “permanently incorrigible.”
“His grandmother, the wife of the victim, testified on his behalf,” Mr. Shapiro said. “A correctional officer spoke of his rehabilitation, his extraordinary record in prison, how he is an incredible worker and tries to get along with everyone.”
In 2012, in Miller v. Alabama, the Supreme Court ruled that automatic life sentences for juvenile offenders — like the one imposed on Mr. Jones — violated the Eighth Amendment. The decision criticized mandatory sentences, suggesting that only ones in which judges could take account of the defendant’s age were permissible.
In Montgomery v. Louisiana in 2016, the court made the Miller decision retroactive. In the process, it seemed to read the Miller decision to bar life without parole not only for defendants who received mandatory sentences but also “for all but the rarest of juvenile offenders, those whose crimes reflect permanent incorrigibility.”
After the U.S. Supreme Court’s decision in Miller, the Mississippi Supreme Court granted Mr. Jones a new sentencing hearing. The trial judge resentenced Mr. Jones to life without parole without saying in so many words that he was incorrigible.
On Tuesday, Mr. Shapiro said more was required. “Settled law,” he said, “recognizes the scientific, legal and moral truth that most children, even those who commit grievous crimes, are capable of redemption.”