Pope Innocent I in 405
“It must be remembered that power was granted by God, and to avenge crime the sword was permitted; he who carries out this vengeance is God’s minister. What motive have we for condemning a practice that all hold to be permitted by God? (Innocent 1, Epist. 6, C. 3. 8, ad Exsuperium, Episcopum Tolosanum, 20 February 405, PL 20,495)
Pope Innocent III in 1210
The secular power can without mortal sin carry out a sentence of death, provided it proceeds in imposing the penalty not from hatred but with judgment, not carelessly but with due solicitude. (Innocent III, DS 795/425)
Pope Paul III, 1534-1549
Pope Paul III excommunicated Henry VIII in 1538, and opened the Council of
Trent in 1545. “…The punishments to be meted out were specified: imprisonment, execution, and confiscation of goods in the case of those condemned to death.” Papal Bull, Licet ab Initio, 1542
Pope Julius III 1550-1555
As a young man Julius was imprisoned on “death row” during the sack of Rome by mercenaries of Emperor Charles VII. Later as a cardinal he tried to persuade convicts to repent but still enforced the death penalty many times.
Pope Pius IV 1559-1565
Reconvened the Council of Trent and shepherded it to conclusion. Pope Pius IV made full use of the death penalty.
Pope Saint Pius V 1566 - 1572
Saint Pius V implemented the reforms of the Council of Trent including the Roman Catechism and promulgated the 1570 Roman Missal used until 1970.
His papal bull of July 13,1566 threatened the death penalty for all who dared to give shelter to murderers or outlaws. Pope Pius V oversaw many executions.
The Roman Catechism of Trent on the Execution of Criminals:
...“The just use of this power, far from involving the crime of murder, is an act of paramount obedience to this Commandment which prohibits
… “The murderer is the worst enemy of his species, and consequently of nature. To the utmost of his power he destroys the universal work of God by the destruction of man, since God declares that He created all things for man's sake. Nay, as it is forbidden in Genesis to take human life, because God created man to his own image and likeness, he who makes away with God's image offers great injury to God, and almost seems to lay violent hands on God Himself”!
Pope Sixtus V 1585-1590 , The Iron Pope
He launched a much needed anti-crime campaign resulting in over 7,000
criminals being executed.
Pope Clement VIII 1592-1605
It was during papacy of Clement VIII that Robert Cardinal Bellarmine wrote an influential book, The Art of Dying Well. Bellarmine’s approach was that the condemned man could actually be rehabilitated by his suffering and repentance, which would transform his execution into an expiation and his death could become a “good” death.
Blessed Pope Pius IX, the longest reining pope. 32 years, 1846 -1878.
Pope Pius IX convened the First Vatican Council in 1869, decreed papal infallibility, and defined the dogma of the Immaculate Conception. He ordered several executions in the Papal States
Pope Leo XIII, 1901
"The death sentence is a necessary and efficacious means for the Church to attain its ends when rebels against it disturb the ecclesiastical
unity, especially obstinate heretics who cannot be restrained by any other penalty from continuing to disturb ecclesiastical order." - Preface to vol. 2 of "Book of Canon Law
Pope Saint Pius X in his Catechism, 1908
“ It is lawful to kill when fighting in a just war; when carrying out by order of the Supreme Authority a sentence of death in punishment of a
crime.” (Answer to question 3 - Are there cases in which it is lawful to kill?)
Pope Pius XII in 1952
“Even when there is question of the execution of a condemned man, the State does not dispose of the individual's right to life … by his crime, he has already dispossessed himself of his right to life.” - Address to the First International Congress of Histopathology of the Nervous System, 14 September 1952, XIV, 328