On the books in most states, the death penalty has been challenged by many, originally on grounds that it violated the Constitutional prohibition against cruel and unusual punishment, and later on the procedural grounds that there were not enough due process protections for defendants accused of capital crimes. In general, it was held that since the sentence was so severe, the law must impose the strictest standards of proof to sentence a defendant to death. Consequently, many states have gone through periods in which the death penalty was held as legal, then illegal, then revised and held as legal, then illegal again, and then further revised and held as legal once more. This shifting status often brought unbalanced—unjust—sentencing. For instance, in many of these states one of two defendants accused of identical unrelated crimes committed within weeks of each other drew the death sentence while the other did not, merely because the statute under which they were sentenced was ruled unconstitutional in the intervening time.

The Supreme Court has since handed down explicit guidelines defining the legal imposition of the death penalty, allowing states a new opportunity to legislate a legal death penalty statute that is less likely to be ruled unconstitutional in the future. This does not mean that the process is not still open to attack. As of this writing, new cases on the death penalty are currently wending their way through the courts to the Supreme Court.