Angela Marinucci, of Greensburg, was only 17 when 30-year-old Jennifer Daugherty was killed in February 2010 at an apartment about 30 miles east of Pittsburgh.
Marinucci's age made her ineligible for the death penalty, which three of five other co-defendants still face. But the Pittsburgh Tribune-Review reports Marinucci now contends her age at the time of the killing also makes her ineligible for a life sentence without parole.
The Supreme Court on Monday ruled that sentencing juveniles to life in prison without parole amounts to cruel and unusual punishment.
Marinucci was convicted of first-degree murder last May.