In the Miller v Alabama ruling, the Supreme Court found that mandatory life without parole sentences imposed on juveniles under the age 18 violate the 8th Amendment’s ban on cruel and unusual punishment. While life without parole sentences can still be imposed on juveniles, the Court noted that these should be rare instances. The Court ruled that judges and juries must consider age, life experience, degree of responsibility and capacity for change when considering sentences for juveniles convicted of murder. The Court also referenced their 2010 Graham v. Florida decision (which held that life without parole for juveniles convicted on non-homicide offenses is unconstitutional) and noted that juveniles should be provided with a meaningful opportunity to obtain release based on demonstrated maturity and rehabilitation.
Read more (in plain english) at SCOTUSblog.
Read the Opinion.