At age 17, a juvenile Simmons planned and committed murder. He was convicted of the crime, which was undoubtedly premeditated. Simmons told his friends that he was planning to murder someone and would be able to get away with it because they were minors. The premeditated nature and heinousness of the crime led the jury to recommend a sentence of death. On appeal to the Missouri Supreme court, Simmons counsel argued that in light of Atkins v Virginia, juveniles under the age of eighteen could not be sentenced to death. The Supreme Court granted certiorari as the state court's decision directly went against the decision of Stafford v Kentucky.
In a 5-4 decision, the Supreme Court affirmed Missouri's state court decision that under the Eight Amendment, a juvenile could not be sentenced to death because that would constitute cruel and unusual punishment. Notably, Justice Kennedy changed his position; now believing that minors cannot be sentenced to death.
Justice Kennedy, writing for the majority, alleged that since Stafford v Kentucky, a national consensus had emerged because the majority of states now bar executions of those under eighteen. Furthermore, no state since the Stafford case had lowered the age below eighteen. Also, because of the imposition of the death penalty has become so infrequent, it is now considered both cruel and unusual.
The majority also argues that only the worst offenders can be ever subjected to death. The lack of responsibility, maturity and development make it impossible for juveniles to be the worst offenders. Second, outside influences affect adolescents more than adults and therefore cannot have the same culpability as adults.
The majority also stresses that amici briefs from the international community prohibiting the execution of juveniles prove the world's attitude against these practices. Being the only country still allowing these...