Jackson (P) accompanied two other boys to a video store to commit a robbery; on the way to the store, he learned that one of the boys was carrying a shotgun. P stayed outside the store for most of the robbery, but after he entered, one of his co-conspirators shot and killed the store clerk. Arkansas charged P as an adult with capital felony murder and aggravated robbery, and a jury convicted him of both crimes. The trial court imposed a statutorily mandated sentence of life imprisonment without the possibility of parole. P filed a state habeas petition, arguing that a mandatory life-without-parole term for a 14-year-old violates the Eighth Amendment. Disagreeing, the court granted the State's motion to dismiss. The Arkansas Supreme Court affirmed. Miller (P) along with a friend, beat P's neighbor and set fire to his trailer after an evening of drinking and drug use. The neighbor died. P was initially charged as a juvenile, but his case was removed to adult court, where he was charged with murder in the course of arson. A jury found P guilty, and the trial court imposed a statutorily mandated punishment of life without parole. The Alabama Court of Criminal Appeals affirmed, holding that P's sentence was not overly harsh when compared to his crime and that its mandatory nature was permissible under the Eighth Amendment. The Supreme Court granted certiorari.