By Jim Melwert

DOYLESTOWN, Pa. (CBS) — A Bucks County judge plans to issue her decision Thursday on a new sentence for a man who’s spent the past 39 years in prison for his part in the brutal, 1978 murder of a classmate. This comes after the U.S. Supreme Court ruled mandatory life sentences for juveniles are unconstitutional.

Defense attorney Stuart Wilder argues, after nearly four decades behind bars, his client, John Lekke, is rehabilitated and should be eligible for parole.

Lekke is now 56. When he was 17 he helped beat 17-year-old Diane Goeke to death. He pleaded guilty and was sentenced to life without parole.

Re-Sentencing Hearing For Man Jailed For Murder As Juvenile In 1978

Lekke took the stand Wednesday and — on direct examination — highlighted activities he’s been involved with in prison, like community college classes, and charity fundraisers. The defense is trying to show that in his 39 years behind bars, Lekke has been a model prisoner.

Prosecutor Jennifer Schorn argues while Lekke may have taken advantage of prison programs, the judge should still take into account the gravity of his crime.

In 1978, Lekke and his friend Bob Buli decided to kill Goeke as she was threatening to tell Buli’s parents she was pregnant with his child for a second time.

The two lured Goeke into the woods, as Buli held her, Lekke smashed a 2×4 over her head, the two then beat her with a pipe, then later that night the put a 200-plus pound piece of concrete over her head.

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