Nathan Walker's new sentence was required by a U.S. Supreme Court decision that juveniles cannot receive life sentences for crimes other than murder even when tried as adults, The Palm Beach Post reported.
Walker, two other juveniles and a young man were convicted of a brutal 2007 rape at a West Palm Beach housing project.
A 35-year-old woman was sexually assaulted by a group of up to nine men, and her 12-year-old son was tortured.
Jakaris Taylor, who also was given a life sentence, is expected to have a new hearing soon. Tommy Poindexter, who was 18 at the time of the crime, was not affected by the Supreme Court ruling, while Avion Lawson, who cooperated with prosecutors, received a 30-year sentence.