Pope Francis has ordered a change to the Catechism of the Catholic Church on the topic of the death penalty: NC Register story.
The death penalty
“2267. Recourse to the death penalty on the part of legitimate authority, following a fair trial, was long considered an appropriate response to the gravity of certain crimes and an acceptable, albeit extreme, means of safeguarding the common good.
Today, however, there is an increasing awareness that the dignity of the person is not lost even after the commission of very serious crimes. In addition, a new understanding has emerged of the significance of penal sanctions imposed by the state.
Lastly, more effective systems of detention have been developed, which ensure the due protection of citizens but, at the same time, do not definitively deprive the guilty of the possibility of redemption.
Consequently, the Church teaches, in the light of the Gospel, that “the death penalty is inadmissible because it is an attack on the inviolability and dignity of the person”, and she works with determination for its abolition worldwide.
 FRANCIS, Address to Participants in the Meeting organized by the Pontifical Council for the Promotion of the New Evangelization, 11 October 2017: L’Osservatore Romano, 13 October 2017, 5.”
Notice that the above teaching takes into account the modern circumstances: “more effective systems of detention have been developed”. Therefore, the Pope is not saying that the death penalty is intrinsically evil. He is not condemning the use of the death penalty, in past times, when systems of detentions were insufficient. And the ability of nations to defend citizens has improved in other ways. For example, modern means of communication and of information storage, processing, and retrieval, have helped to reduce crime rates. Law enforcement can communicate more efficiently and keep track of persons with a criminal record more easily.
So the death penalty is not intrinsically evil. And it may be the case, in the future, that society changes such that the death penalty becomes necessary, as for example, during a world war, when society is engulfed in chaos. So this development of doctrine does not rule out future use of the death penalty, morally.
Also, it is possible to faithfully dissent from this teaching, since it is based in part in an evaluation of the circumstances of the act, and is not solely based on doctrines of faith or morals.
Colorado Catholic Conference: “In some moral matters the use of reason allows for a legitimate diversity in our prudential judgments. Catholic voters may differ, for example, on what constitutes the best immigration policy, how to provide universal health care, or affordable housing. Catholics may even have differing judgments on the state’s use of the death penalty or the decision to wage a just war. The morality of such questions lies not in what is done (the moral object), but in the motive and circumstances. Therefore, because these prudential judgments do not involve a direct choice of something evil, and take into consideration various goods, it is possible for Catholic voters to arrive at different, even opposing judgments.” [Moral Principles for Catholic Voters, p. 2]
Cardinal Joseph Ratzinger: “Not all moral issues have the same moral weight as abortion and euthanasia. For example, if a Catholic were to be at odds with the Holy Father on the application of capital punishment or on the decision to wage war, he would not for that reason be considered unworthy to present himself to receive Holy Communion. While the Church exhorts civil authorities to seek peace, not war, and to exercise discretion and mercy in imposing punishment on criminals, it may still be permissible to take up arms to repel an aggressor or to have recourse to capital punishment. There may be a legitimate diversity of opinion even among Catholics about waging war and applying the death penalty, but not however with regard to abortion and euthanasia.” [Worthiness to Receive Holy Communion, General Principles, n. 3]
In my opinion, the death penalty is still necessary, moral, and fitting in present-day circumstances, for certain very grave crimes, such as mass murder, terrorism, and for persons who are dictators or crime bosses (who cannot be effectively incarcerated). I would also point out that present-day prison systems have many aspects that make them inhumane. Some prisoners would perhaps prefer a punishment of death, over a very lengthy sentence in a prison that daily offends against human dignity and good morals.
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