Final answer:
Ring v. Arizona mandated that a jury must determine any factors that increase a defendant's punishment in death penalty cases. This has led to significant changes in capital sentencing procedures across the United States and is part of a broader trend of the Supreme Court narrowing the death penalty's application.
Step-by-step explanation:
The case of Ring v. Arizona has had a significant impact on death penalty cases. In Ring, the Supreme Court ruled that a jury, not a judge, must find each fact necessary to impose a death sentence. This means that any factor that could increase the punishment beyond the prescribed statutory maximum has to be submitted to a jury and proved beyond a reasonable doubt, a procedure not followed in Arizona at the time of the Ring decision. This decision has led to the restructuring of sentencing procedures in capital cases throughout the United States. Moreover, Ring v. Arizona is one example of many where the Supreme Court has systematically narrowed the application of the death penalty, such as disallowing capital punishment for defendants with cognitive disabilities, juvenile offenders, and those convicted of crimes that did not result in death, except for certain cases of murder. These rulings reflect a broader judicial and public shift against the use of the death penalty, influenced by factors such as wrongful convictions revealed by DNA evidence, a decline in violent crime, and changes in state laws and policy.