The death penalty issue is almost too vast to narrow to a single sub-issue, but in this forum, it seems appropriate, and thus, the question of whether the death penalty should be used against the insane and mentally retarded.
In Ford v. Wainwright, 477 US 399 (1986), the Unites States Supreme Court considered the death penalty as to an insane person. It found that consideration must be given to “objective evidence of contemporary values”, as well as “the kinds of punishments that were considered cruel and unusual at the time that the Bill of Rights was adopted in 1789″. The Court recognized that”evolving standards of decency” mark the progress of a maturing society. Therefore, if at common law, it was considered extremely inhumane and cruel to execute someone who was not responsible for his own acts, the final ruling that it is unconstitutional to carry out the death penalty upon an insane person is appropriate.
A few years later, in Penry v Lynaugh, 492 US 302(1989), the Court took up the issue as to mentally retarded persons and concluded that it is not unconstitutional to execute someone who is mildly to moderately mentally retarded simply by virtue of their mental retardation, and left the determination up to a case-by-case analysis.
There was and still is a lack of public consensus and the Court was influenced by this. In the end, the greatest weight was given to the fact that there are varying degrees of mental retardation, some of which do not inevitably lack the cognitive, volitional, and moral capacity to act with the degree of culpability associated with the death penalty. Perhaps it is best that there is no public consensus because the public opinion does have a huge impact on the analysis and we know that the history of public opinion reveals an interest in the death penalty and opinion of it, that waivers over time. The public has a tendency to change its mind over time, according to the passions of the time. This does not seem acceptable when it comes to putting a person to death. Perhaps the death penalty issue is best served by a categorical imperative that can apply in all contexts across time, “thou shall not kill.”