Pennsylvania has the most inmates given life without parole as teens, a sentence that the U.S. Supreme Court has cited as unconstitutional — if tried after 2012. 

A 2012 Supreme Court decision, Miller v. Alabama, said that life without parole is an unconstitutional sentence for those under 18 years old. This week, the court refused to hear a case that would allow life-without-parole sentences to be revisited for more than 450 Pennsylvania inmates sentenced before 2012. As a result, Pennsylvania courts will not allow those sentences to be challenged. 

Six states have instituted retroactive enforcement of the decision in Miller v. Alabama. Pennsylvania joins Minnesota and Florida in banning challenges to inmates currently serving life-without-parole who were sentenced when teenagers.  

In Miller v. Alabama, the Supreme Court justified its decision by citing that children's and teens' brains and decision-making capacities are not fully developed, and they have "greater prospects for reform" than adults. The decision did not address the rights of the 2,600 inmates already serving life without parole for crimes committed as children and teens.

The juvenile justice system disproportionately affects Black, Latino and Native American teens. According to 2011 Office of Juvenile Justice data, 77 percent of juvenile arrests involved teens of color.