The Supreme Court of the United States held that executing mentally retarded defendants violated the cruel and unusual punishment clause of the Eighth Amendment to the United States Constitution.
Atkins v. Virginia, 534 U.S. 304 (2002)
The Cruel and Unusual Punishment Clause of the Eighth Amendment Prohibits the Execution of Mentally Retarded Defendants: Atkins v. Virginia,
Duq. L. Rev.
Available at: https://dsc.duq.edu/dlr/vol41/iss4/14