Final answer:
A death sentence requires consideration of mitigating evidence, including cognitive disabilities, age, and lack of intent to kill, and must meet the 'beyond reasonable doubt' standard. Mitigating factors must be weighed against aggravating factors, and automatic death sentences are unconstitutional.
Step-by-step explanation:
Before a death sentence can be imposed, certain types of mitigating evidence must be considered by the court. This evidence serves to provide reasons why the death penalty should not be applied. The U.S. Supreme Court has established a number of precedents that set the boundaries for when the death sentence can be imposed. For instance, in the case of Proffitt v. Florida, the constitutionality of Florida's death penalty statute that sentencing must involve a comparison of aggravating factors to mitigating factors. Moreover, individuals with cognitive disabilities, juveniles at the time of the crime, or those who did not intend to kill cannot be sentenced to death, as per Roper v. Simmons and Atkins v. Virginia. In a capital homicide case, the standard of proof must be ‘beyond reasonable doubt’ to impose the death penalty. Situations where the accused did not actually kill, attempt to kill, or intend that a killing take place, as in Enmund v. Florida, may not result in a death sentence. Similarly, statutes that mandate the death penalty without consideration of specific circumstances of the crime have been struck down, promoting the nuanced application of capital punishment and safeguarding against overly broad or arbitrary imposition.