In the 2001 case Daryl Renard Atkins v. Virginia, the U.S Supreme Court ruled that executing individuals with intellectual disabilities violates the Eighth Amendment's prohibition on cruel and unusual punishment. The case involved Daryl Atkins, a man with an IQ of 59 who was convicted of abduction, armed robbery, and capital murder. Despite his low IQ indicating severe mental impairment, he was sentenced to death by a Virginia court. However, in a landmark decision (6-3), the Supreme Court overturned this sentence stating it violated constitutional rights against cruel and unusual punishments due to Atkins' intellectual disability status.

In the dissenting opinion for Daryl Renard Atkins v. Virginia, Justice Scalia, joined by Chief Justice Rehnquist and Justice Thomas, argued that the majority's decision to prohibit execution of mentally disabled individuals was not based on a national consensus but rather on their own personal beliefs. They contended that it is inappropriate for the court to determine what constitutes "cruel and unusual punishment" based on evolving standards of decency; instead, this should be left up to legislatures. The dissenters also criticized the majority's reliance on international law in making their determination as irrelevant because American law does not consider foreign laws or treaties unless they are explicitly incorporated into U.S. law through legislation or treaty ratification.