III. On the Killing of an Unjust Aggressor

Is it lawful to kill an aggressor against one's life? - Anyone can kill an unjust aggressor against his life, with the moderation of blameless defense. Thus S. Thomas, and he confirms his thesis from the fact that in Exod. 22:2 it is lawful to kill a nocturnal thief. Therefore much more, he says, is it lawful to defend one's own life. Then, all laws and all rights proclaim that force may be repelled by force. Finally, nature itself teaches that there is in man a true right of defending his own life if it is unjustly attacked, and of preferring it to the life of the unjust aggressor, who from his own malice has cast himself into such danger. And this holds not only for secular persons, but also for clerics themselves and religious; for the right of defense is implanted in each one by nature. If it were otherwise, weapons would be supplied to injustice, to the slaughter of the good, and to the overthrow of commonwealths. Hence the Roman Catechism, n. 8, attributes this right to all without distinction. C. Significasti 18 de Homic. vol.; C. Si vero de Sent. exc.; C. L. 2367; S. Th. 1. 2, q. 64, a. 7; L. 380.

Note: Can; for no one is bound to kill an aggressor. It is a dreadful means for conserving one's own life; but lawfully and praiseworthily someone can permit his own killing, lest another be deprived of temporal and eternal life. Make exception: 1. When the life of the one attacked would be necessary and very useful to the common good. 2. When he himself would be in mortal sin, because then he would be altogether bound to defend himself. L. 380.

With the moderation of blameless defense, which is situated in these three conditions: 1. That the killing of the aggressor not be done for vengeance, since this does not belong to private persons; nor from hatred, since this would be opposed to charity; but only for repelling injury and force, or for defense of oneself. 2. That one who suffers aggression not use greater violence than is necessary for avoiding death; and therefore, if he can free himself from the unjust aggressor by fleeing or only by wounding, he cannot kill; otherwise he would kill unjustly, and would be bound to restitution proportionate to the excess, since he would exceed the right granted by nature. By fleeing; otherwise charity is injured, though not justice. For is there any right in the unjust invader that the other should flee? By fleeing; provided this can be done without danger, and, if the matter concerns a noble man or a soldier, perhaps also without grave harm. 3. That the unjust aggression actually, morally speaking, be brought, that is, be so impending that one cannot repel it except by using force. For if by striking or killing he forestalls an aggression scarcely probable, he himself becomes the aggressor of another's life, not the defender of his own. Impending: yet it is not to be awaited until the other already begins to harm. Otherwise defense would already be ineffectual. C. Significasti 18 de Homic. vol.; C. L. 2367, 2370; Struggl 17, 20, 30; Ithur. Cas. 40, nn. 9-10; Lugo d. 10, n. 161; L. 380, 381, 387, 388.

Is the same lawful for preserving the integrity of life? - It is lawful with the same moderation to kill an unjust aggressor also for the defense of members. Proof: 1. from the common opinion of theologians. 2. Because each one has the right of preserving a good most necessary to life for himself, even with danger to the life of another, to which danger the other from his own malice exposes himself, provided another means is lacking and the death of the aggressor is not intended. C. L. 2367; L. 380, 398.

Is the same lawful for defending chastity? - It is lawful for a woman to defend herself by killing the invader of her modesty. Proof: 1. from the common opinion of theologians. 2. Because the woman uses her own natural right, by which it is lawful to repel force by force, and she is more bound to provide for herself than for the life of another; for she exposes herself to the danger of consenting to the act of sin by permitting herself to be oppressed. Besides, if it is lawful to kill an invader of goods, how much more an invader of modesty, since it is a good of a superior order? Hence, although a girl is not bound to kill the invader, but can conduct herself passively, because chastity is not lost unwillingly, nevertheless she is not obligated to do this, both because even material bodily integrity itself is a very great good, and because there is present the danger of shame, which is more grave than death for good women. C. L. 2367; L. 368, 386.

Note: Here theologians rightly observe that it is lawful for a girl not only to repel the aggression in the act in which she suffers it, but also afterward she can strike the aggressor with slaps, fists, a rod, staff, and similar blows minimally dangerous, so that thus she may show her displeasure and constancy, and the aggressor may more easily depart and not return. Moreover this, provided it is done immediately after the injury received and never for vengeance, is not only to be permitted, but also altogether to be counseled to women. Struggl 28; L. 386; Lugo d. 10, n. 196.

Is the same lawful for defending goods of fortune? - It is lawful to defend goods of fortune of great importance with the killing of a thief, if they cannot otherwise be retained. Proof from the common opinion of theologians, which S. Th. 2. 2, q. 64, a. 7 supposes. Besides, because the precept of charity does not oblige one to prefer the goods of a neighbor of a higher order, unless when he is in extreme necessity, but not when he himself of himself, voluntarily and from his own malice, meets the danger of death, as happens in the case. C. L. 2367 seqq.; C. B. 227 seqq., 904; L. 380, 382; Struggl 23; E. M.

Note: Of great importance; for it is not lawful to kill a thief taking away a thing of lesser importance, because charity then prohibits us from inflicting a most grave damage on our neighbor for our own light damage, although he voluntarily exposes himself to its danger. And indeed our damage is only light, whether the thing taken away is considered, which is of lesser importance, as is supposed, or the injury which is had in that taking away is considered, and consequently the contempt and dishonoring which follows that injury. For who is thought to be gravely dishonored because a thief has violently snatched some thing from him?

Nevertheless, even in this case, if precisely the force which is brought against the owner guarding his own thing, although of lesser importance, is considered, it will always be lawful for him to repel force by force, but with the moderation of blameless defense. The reason is that "when someone thus defends his own things, regularly he defends at the same time his own person, which he exposes to danger for the defense of his things." Molina tom. 4, tr. 3, disp. 16, n. 4. Besides, the public good itself demands this. Otherwise the impunity of crimes would render the wicked more audacious for doing harm. C. L. 2367; Laymann l. 3, tr. 3, c. 3, p. 3, n. 4.

Generally speaking, however, those goods are judged to be of great importance, which, if taken away, would leave someone without sustenance for himself and his own; theologians of grave note, among whom is Card. de Lugo, teach that even those things can be given this name whose loss would bring a notable harm to the owner according to the quality of the person. Although it must not be denied either that some gravity of damage must be admitted, absolutely grave with respect to all, and far greater than that which suffices for mortal theft. Therefore, absolutely speaking, the sum of 4 or 5 gold coins certainly does not suffice; today, 40 or 50 lire. But the sum of 40 or 50 gold coins seems to suffice; today, 400 or 500 lire. L. 382, 383, 384, 385; Struggl 23, 24; E. M.

Is the same also lawful for defending honor? - It is not lawful indeed to kill an invader of honor if honor is attacked by words only. For, since the injury can, must, and usually is then repelled otherwise, a striking and killing has the nature not of defense, but of private vengeance. Likewise it is not lawful to kill an invader of honor if honor is attacked by deeds after the deed itself. For even an injury to the aggressor after the deed does not have the nature of defense, but of private vengeance. But it is lawful, with due moderation, to defend oneself against an invader even of honor, if it is attacked by deeds, for example, by a slap or kicks, or a staff, before the deed itself. The reason is that all laws permit force to be repelled by force. Therefore he is not to be reproved who wishes to use that right which all laws permit for guarding a good great in the estimation of men, which is better than a thousand precious and great treasures, Ecclus. 41:15, and who defends himself with fists and also with kicks and a staff. C. L. 2367; Lugo d. 10, n. 166; La-Croix 803; Struggl 25, 26, 31; L. 380, 381, 382, 391; S. Th. 2. 2, q. 41, a. 1; E. M.

Is the aforesaid defense lawful, if it concerns others? - Some private person can defend the life, goods, and modesty of a neighbor, even by the killing of an unjust aggressor. Proof: 1. from the common opinion of theologians. 2. "Because just as the innocent neighbor himself can defend himself by killing the aggressor, so it is lawful to cooperate with him in a lawful thing which he himself can do, and to help him." Lugo de Iust. d. 10, n. 201; C. L. 2368; Struggl 29; L. 389, 391; S. Th. 2. 2, q. 60, a. 6 ad 2.

Note: Some private person; for it is certain that Princes, magistrates, and soldiers, who have been specially hired for the defense of citizens, are bound to this. C. L. 2371. These are bound even with danger of their own life, where the matter concerns turning away a public evil from citizens; but where the matter concerns only the life of some private person, they are not bound to protect it with so great an inconvenience. Can; for it is more probable, at least speaking generally, that he is by no means obligated to such defense of an innocent man with the killing of the unjust aggressor; and this both because the precept of charity does not seem to oblige in that case, since it is rather better to avoid the eternal death of the aggressor himself; and because in the killing of another, a grave inconvenience can never be avoided, for example, because of fear of enmities, or of public justice, or even because of the horror conceived in staining one's own hands with human blood. At least speaking generally; for make exception: 1. If the one invaded would be necessary for the public good, which each one is bound under grave obligation to care for. 2. If he is father, son, wife, or brother, whom piety itself obliges one altogether to protect.

If the matter concerns an invader of another's modesty, understand this provided that the woman does not furnish her consent to the invader, but positively resists him; otherwise to kill the invader would not be to repel force by force, since there is no injury where there is consent. Lessius, Sporer, and others make exception if the one attacked is very closely related to you; then, they say, before the deed you can still kill the invader, although the one attacked consents; for in that case you repel the injury which redounds upon you. L. 389-392.