Although the separate opinions by Justices Brennan and Marshall stated that the death penalty itself was unconstitutional, the overall conclusion in Furman was that the specific death penalty statutes were unconstitutional. That decision by the Court opened the door for states to revise death penalty statutes to eliminate the problems cited in Furman. Advocates of capital punishment began proposing new statutes that they believed would end arbitrariness of capital sentences. The states were led by Florida, which rewrote its death penalty statute only five months after Furman. Shortly after, 34 other states enacted new death penalty statutes. To address the unconstitutionality of unguided jury discretion, some states removed all discretion by mandating capital punishment for those convicted of capital crimes. This practice was ultimately found unconstitutional by the Supreme Court in Woodson v. North Carolina (428 U.S. 280 ).
Other states began to limit discretion by providing sentencing guidelines for judges and juries considering death sentences. Such guidelines allowed for the introduction of aggravating and mitigating factors in sentencing. In 1976, the Supreme Court approved these discretionary guidelines in Gregg v. Georgia (428 U. S. 153), Jurek v. Texas (428 U. S. 262), and Proffitt v. Florida (428 U. S. 242), collectively referred to as the Gregg decision. This landmark decision held that the new death penalty statutes in Florida, Georgia, and Texas were constitutional, thus reinstating the death penalty in those states. Additionally, the Court maintained that the death penalty itself was constitutional under the Eighth Amendment.
In addition to sentencing guidelines, the Court approved three additional reforms in the Gregg decision. The first was bifurcated trials, in which there are separate deliberations for the guilt and penalty phases of the trial. Only after the jury determines that the defendant is guilty of capital murder does it decide in a second trial whether the defendant should be sentenced to death or given a lesser sentence of prison time. Another reform was the practice of automatic appellate review of convictions and sentence. The final procedural reform was proportionality review, a practice that assists states in identifying and eliminating disparities in sentencing. The state appellate court can use this process to compare the sentence in a case being reviewed with other cases within the state, to see if it is disproportionate. Because the reforms were acknowledged by the Supreme Court, some states wishing to reinstate their death penalty sentences included them in revised statutes. However, inclusion was not required by the Court. Therefore, some of the resulting new statutes include variations on the procedural reforms found in Gregg.
The ten-year moratorium on executions that began with the Jackson and Witherspoon decisions ended on January 17, 1977, with the execution of Gary Gilmore by firing squad in Utah. Gilmore did not challenge his death sentence. That same year, Oklahoma became the first state to adopt lethal injection as a means of execution, though it would be five more years until Charles Brooks became the first person executed by lethal injection in Texas on December 2, 1982.