In Gregg v. Georgia (1975), the U.S Supreme Court ruled that capital punishment did not violate the Eighth Amendment's prohibition of cruel and unusual punishment, thereby reinstating the death penalty in America. The case involved Troy Leon Gregg who was sentenced to death for armed robbery and murder in Georgia. He argued that his sentence was "cruel and unusual" as it violated his Eighth Amendment rights. However, a 7-2 majority on the court disagreed with him, stating that if carefully employed, capital punishment may deter certain serious crimes more effectively than life imprisonment thus serving social purposes sufficiently substantial to justify its imposition. This decision marked an end to a de facto moratorium on executions which had been in place since 1967 while courts grappled with questions about fairness in sentencing procedures.

In the dissenting opinion for Gregg v. Georgia, Justice Brennan and Justice Marshall argued that capital punishment is always cruel and unusual punishment in violation of the Eighth Amendment. They contended that death penalty does not deter crime more effectively than life imprisonment, thus failing to serve any penal purpose. Furthermore, they believed it was inherently degrading to human dignity to kill a person as a form of state-sanctioned retribution or deterrence. The justices also expressed concern about racial disparities in sentencing and the risk of executing innocent people due to errors in criminal justice processes. Additionally, they criticized the majority's reliance on public opinion polls showing support for capital punishment because constitutional rights should not be determined by popular vote.