Section — Noldin, Summa of Moral Theology
Section 6. Defect of Lenity.
489. From Defect of Lenity these are irregular: a. a judge who has pronounced a sentence of death; b. one who has undertaken the office of executioner and their voluntary and immediate ministers in executing a capital sentence.1
From the mind of the Church it is plainly unfitting that one who has been the cause of another's death, even justly, should represent the person of Christ the most meek, who never injured anyone. Therefore this irregularity is established as coming from a twofold head: from a sentence of death and from the execution of a capital sentence. These are usually called irregularities from defect of lenity or meekness; but this defect is contracted only after baptism.
A judge bearing a sentence of death is irregular: a. if the judgment is just, for if the judgment is unjust, irregularity is contracted not from defect of lenity but from the delict of homicide; b. if death has really followed, even without shedding of blood; c. in a case in which several, a college of judges, concur in bringing the sentence of death, if they have efficaciously influenced it; d. if he is baptized.
The executioner who executes a pronounced sentence of death, and his immediate and voluntary ministers, are irregular: a. if they act by force of office; b. if they in reality execute the capital sentence; c. as to ministers, if they act voluntarily; d. if they are baptized.
Soldiers who are led to kill by arms a soldier punished with death by legitimate authority after sentence of execution are not irregular. Not the leaders, who condemn to death, but soldiers, because they do not act voluntarily, since they have been ordered, are immune from irregularity.2
1 Cn. 984, 6, 7.
2 Leitner, l. c., p. 161.