Atwood v. Weems was a United States Supreme Court case that addressed the issue of cruel and unusual punishment. The case involved a man named Peter Weems, who was convicted of falsifying a public document in the Philippines. As punishment, Weems was sentenced to fifteen years of hard labor, twelve years of solitary confinement, and a fine of four thousand pesos. The Supreme Court heard the case and ruled in favor of Weems. The Court held that the punishment imposed on Weems was cruel and unusual and violated the Eighth Amendment of the United States Constitution. The Court reasoned that the punishment was disproportionate to the crime and that it was not necessary to deter future criminal behavior. The Court also noted that the punishment was not in line with the standards of decency that had evolved in the United States. The Court concluded that the punishment imposed on Weems was cruel and unusual and therefore unconstitutional. The decision in Atwood v. Weems established that the Eighth Amendment of the United States Constitution prohibits cruel and unusual punishment. The decision has been cited in numerous cases since then and has been used to protect individuals from excessive punishments.

In Atwood v. Weems, the Supreme Court was tasked with determining whether a sentence of cadena temporal imposed by a Philippine court on an American citizen for embezzlement constituted cruel and unusual punishment in violation of the Eighth Amendment. The majority opinion held that it did not, as there were no circumstances present which would make such a sentence so disproportionate to the offense committed as to shock public conscience or violate any principle of justice recognized by civilized nations. Justice Harlan dissented from this opinion, arguing that while he agreed with much of what was said in the majority opinion regarding punishments being determined according to local customs and laws, he felt that when considering punishments inflicted upon citizens who are subject both to foreign law and their own Constitution they should be judged against standards set forth therein rather than those established elsewhere. He further argued that even if one accepted all other aspects of the majority's reasoning, its conclusion still failed because it overlooked certain facts about cadena temporal which made it particularly harsh: namely its indefinite duration and lack of opportunity for parole or pardon.