(a) Thus, a general suspension of the capital punishment is lawful in a community whose members are peaceful and not inclined to violence or other crimes subversive of law and order. Whether such ideal conditions exist today may be doubted, and indeed some countries that abolished the death penalty have found that this proved an incentive to crime and they were forced to restore the former laws.
(b) A particular exemption from capital punishment is lawful, when there are good reasons recognized by law for commutation or clemency. This has been the practice of governments throughout history, and is justified when it furthers the common welfare, or at least shows mercy to a deserving individual without harm to society. But a judge has to condemn when the law and the facts call for condemnation, and the authority in whom the pardoning power is vested has to use his power prudently, lest he encourage lawlessness.
1822. It is not morally lawful to put criminals to death unless the following conditions are present:
(a) the crime must be external and of such a character that the public welfare requires the supreme punishment, either on account of the enormity of the act (e.g., murder), or on account of its danger (e.g., sleeping at one’s post in time of war). Further, the crime must be certain and sufficiently established, for, since the punishment should fit the offense and the law presumes innocence until guilt is proved, no one should be sentenced to death except for a serious and certain crime. The Fifth Amendment to the American Constitution declares that no person shall be deprived of life, liberty or property without due process of law;
(b) the sentence of death and its execution should be performed by those who have public authority for these acts and in the manner required by law. For capital punishment is a means of self-defense used by society, and its use pertains there fore to the representatives of society. Moreover, if private individuals exercised this function, accused persons would not receive the consideration of their rights or the opportunity of defense due them, and the public peace would be overthrown by murders of revenge committed in the name of justice.
(c) the penalty should be carried out in a humane and Christian manner, as is manifest. The convicted man should be allowed time and opportunity to make his peace with God and, if possible, to say farewell to relatives. Slow and agonizing forms of killing are of course entirely wrong, no matter how wicked the criminal who is being executed. The American law and other laws do not permit a pregnant woman to be executed until she has delivered her child.
1823. Unlawful Killing of Offenders.—The killing of offenders is, therefore, unlawful in the following cases:
(a) when the offense is not serious or fully deliberate (e.g., involuntary manslaughter), or when it has not been sufficiently established (e.g., if it is not certain that the supposed victim of murder is dead or that he died from a homicidal act). In civilized countries today the law inflicts capital punishment only for the most serious crimes, and the State has to prove its case beyond reasonable doubt before the punishment can be decreed. But in the past death was often the penalty for horse- or sheep-stealing, or even smaller offenses, and in times of excitement men have sometimes been sentenced to death without a fair trial;
(b) when the sentence of death is not pronounced or executed legally. Those who lynch the perpetrators of heinous crimes are often in good faith, especially if the processes of the law are too slow or uncertain, but since they act without authority, their deed is really murder. The same is true of a husband who kills his wife taken in adultery, of the relative of a seduced girl who kills the seducer, of an officer of the law who unnecessarily or without authorization kills a man sentenced to death when the latter is trying to escape. The State has the right, though, to declare a notorious malefactor outlawed, and thus to give to private citizens the right to take him dead or alive, or to kill him on sight; but it is clear that the exercise of this right is a dangerous remedy and one to be used sparingly;
(c) when the mode of killing or the circumstances are repugnant to Christian feeling. Today capital punishment is generally inflicted in a humane manner, but history records many cruel forms of execution, as when men were hanged, drawn and quartered, or burned at the stake, or put to death amid the jeers and curses of the populace.