Earlier this year, Mario Casciaro was found guilty of first-degree murder in the 2002 death of Brian Carrick.
Carrick was 17 years old when he disappeared from a Johnsburg grocery store owned by Casciaro's family.
Prosecutors say Casciaro and convicted felon Shane Lamb carried out the killing.
Carrick's body was never found.
His family says the sentence is fair.
Casciro's family says he's innocent.
An earlier murder trial for Casciaro ended in a mistrial.