The U.S. Supreme Court Monday took two cases to decide whether a juvenile's sentence of life in prison for murder constitutes cruel and unusual punishment prohibited under the Eighth Amendment.

The high court has been chipping away at the types of sentences minors receive. Last year, the justices said that life in prison without parole is unconstitutional for minors convicted of anything but murder.

The death penalty for teenagers younger than 16 was abolished in 1988, while capital punishment for those younger than 18 was done away in 2005.

These two cases focus on young teens below the age of 14. Lawyers for the two men sentenced to die in prison say that the characteristics of 14-year-olds that make life in prison unconstitutional for crimes other than homicide are just as much in operation when a murder is involved.

There is no reason to imagine that fatal acts committed by a child of thirteen or fourteen are typically less impulsive, more farsighted, more cognizant of likely consequences, less peer-influenced, or more susceptible to self-control than nonfatal criminal acts, lawyers from the Equal Justice Initiative wrote in a petition to the Supreme Court.

Life Sentences for Juveniles

The Equal Justice Initiative said their clients are among the 73 juveniles 14 years old and younger in the U.S. who have received lifelong prison sentences.

Yet when the Supreme Court decided that these sentences are unconstitutional for juveniles, the justices left unanswered the question about young teenagers who commit or are charged in homicides.

This Court will inescapably be called upon, sooner or later, to determine whether sentences such as these violate the Constitution's ban on cruel and unusual punishments, lawyers for one of the convicted teens wrote in a court petition.

One case that will be argued before the justices concerns an Arkansas teen, Kuntrell Jackson, who at 14 years of age was sentenced to live in prison for being an accomplice to an impromptu robbery in which a shop attendant was shot to death.

The other case involves Evan Miller of Arkansas, who was one of three teens who beat a man and set fire to his home, resulting in death from smoke inhalation.