In The Ethics of Liberty Murray Rothbard made the remark that punishment theory has been scarcely treated by libertarians. The very same thing could be said for the theory of defense. If there has been little attempt by libertarians to determine what sanctions may be taken against an invader of property of another, there have been just as few attempts to determine what means may be used to thwart such an invader.
Rothbard himself devoted a chapter of The Ethics of Liberty to each of these two questions, but then spent a number of paragraphs in the chapter on defense discussing punishment instead, and so himself treated the latter question even more briefly than the former. This brief treatment of defense in The Ethics of Liberty is inspirational, but underdeveloped and insufficient.
In his treatment of defense Rothbard first poses a question of how extensive one’s right to defense of person and property is. He then proposes a basic answer: “Up to the point at which he begins to infringe on the property rights of someone else.” This can scarcely be argued with, for it is simply the principle of non-aggression restated. To infringe upon the property rights of another is indeed impermissible in any circumstances.
Rothbard’s elementary answer is useful in that it settles the matter of how much force may, in the conduct of defense, be brought to bear against people other than the aggressor. The answer is none at all. The non-aggression principle does not permit for any amount of “collateral damage” against third parties. Any act of intimidation, fraud or violence against people other than the aggressor carried out under the veneer of repelling aggression is in fact an act of aggression in its own right, and does not fall under defense.
There is one matter Rotbard’s basic answer does not resolve, however. That is, the question of how much force may in the conduct of defense be brought to bear against the aggressor himself? If there is a right to self-defense — and Rothbard showed that for libertarians there has to be — then there can only be one answer. Against the aggressor, the aggressed-upon may use up to exactly the amount of force that is necessary to thwart the aggression.
As Rothbard notes, if an individual has an absolute right to his justly-held property then he has an absolute right to keep that property. Accepting legitimacy of property is diametrically opposite to the position of radical pacifists who deny the legitimacy of defensive violence, usually on humanitarian grounds. It is perfectly legitimate to consider the existence of defensive violence and the physical harm wrought upon the aggressor by their chosen victim as a tragedy, one that is just as great as the violence by the aggressor. However, that is a matter of personal taste and can not take precedence over that which is objectively true.
The truth that is not subject to opinion is that as far as an innocent victim is concerned neither of these ‘tragedies’ need to occur. It is in fact the criminal alone who by initiating aggression makes certain that either one, or the other ‘tragedy’ will take place. And it is the criminal who forces a victim that has the means for a successful defense using violence (by no means are all victims of crime this fortunate) into position of having to decide which of the two possible tragic outcomes shall occur.
What is more, by placing the victim in front of such a choice the aggressor authorizes the victim to take whatever violent measures against him are necessary to interrupt his assault. The criminal effectively makes a demand upon the victim — that the victim can not escape — to either relinquish property in itself and accept harm to itself, or to employ defensive violence against the aggressor that will enable it to keep possession of its property. Since the aggressor has no right whatsoever to demand the former, he may not object when the victim chooses the latter option instead. Because in this way the attacker effectively extorts the violence against himself from his target, he therefore has no grounds to object against it.
Naturally the level of violence employed by the target of the aggressor, or his agents, may not be excessive. The aggressed-upon may use only as much violence as is absolutely necessary to keep his property. Any violence beyond that may not be deemed as having been extorted by the aggressor. Such violence against the initial aggressor — in excess of what is necessary for a successful defense — may be either legitimate (retributive), or illegitimate (aggressive), but determining which is a question for the theory of punishment to resolve, and not a matter of self-defense proper.
It is important to understand that the right to self-defense and the right to retribution are distinct from one another. They are governed by different principles. What magnitude of force is permitted in defense is governed by the principle of the least, sufficient force. How extensive an application of force is appropriate in punishment is determined by the principle of proportionality. There is no way in which the principle of proportionality affects the right to self-defense. Attempting to force upon self-defense the ill-fitting straitjacket of proportionality would mean erecting arbitrary constraints to defense that are ultimately just as indefensible as the across-the-board objections to self-defense by radical pacifists.
To illustrate this point let us first conceive of a crime that has irreparable consequences for the victim, but for which the proper punishment falls short of the death penalty. Let us imagine a moderately severe physical assault that results in life-long chronic pain fits these criteria. Now let us say that John attacks Joe unprovoked, determined not to stop until he inflicts on the latter a battering of this sort. Finally let us say that Joe is in a possession of a crystal ball and therefore knows, firstly that he may not withstand the ferocity of John’s attack other than by quickly pulling a pistol and shooting him in the chest which is easily fatal, and secondly that failing to do that will end in some lasting physical damage for him, but will not be life-threatening.
In such a case is it within Joe’s rights to defend himself in the only way that will prevent him from suffering irreparable damage to his body? Those who uphold property rights must see that it is. Since Joe has a right to his body, he has a right to keep his body intact. He may not be compelled to give up the function of his body for the sake of someone else, least of all someone who attacks him unjustifiably.
Those who would impose the notion on proportionality on defense, however, must disagree. Since the punishment for an assault of this severity would not be to end the aggressor’s life, the victim must therefore likewise stop short of using lethal force in the course of defense. In other words any proponents of proportion in defense would impose on Joe an arbitrary limit to acceptable means of defense that would preclude him from defending himself successfully. They would demand of Joe to accept aggression against himself and deny he has an absolute right to his body. They would assert Joe owns his body only in as much as he is able to restrain John without hurriedly shooting him — which he is not.
Thus the proponent of proportionality in defense stands on no less shaky grounds than does the pacifist. Only where the pacifist would deny the right to self-defense across the board, the proportionalists would deny such a right only in some cases, usually where the aggressor refrains from the most horrible kind of assault, but is sufficiently ferocious and powerful in comparison to its victim, so that the latter is relatively unable to thwart the aggressor except with the most extreme means available.
It is easy to see where the proportionalist goes wrong. It is one thing to see the greater physical damage against the aggressor, as a greater tragedy, than what would have been lesser damage inflicted upon the victim. This, however, is a matter of taste and may not take precedence before that which is objectively true — that no one may compel innocent victims of crime to relinquishing their right not to be harmed by aggression. As far as the victim is concerned neither the ‘lesser tragedy’ of injury suffered by the victim, nor the ‘greater tragedy’ of the death of the attacker need to occur. It is only the attacker who creates the situation that either of them must, and entrusts the victim with the means of successful defense to decide which one shall it be.
Imagine a woman of slight build whose rape at the hands of a powerfully-built man is imminent, unless she manages to use kill-o-zap — a weapon whose every shot is always lethal — that is within her arms’ reach against the attacker. In this scenario, insistence that the aggressed-upon woman limits her attempts at defending herself to only such measures which are somehow “proportional” would bar her from using the 100% lethal weapon, and demand of her to to face the attacker barehanded, rather than end his life. In other words it would demand of her to subject herself to a perfectly preventable atrocity for the sake of the well-being of the aggressing party. It would be tantamount to denying she has an absolute right to never be raped.
Just as it absurd to assert a man has a right to his property, but not to defend it, it is absurd to assert the aggressed-upon individual has a right to defend it, but only with ineffective means that will not actually enable him to recoup his losses or avoid incurring them. If a man has a right to defend himself at the expense of the well-being of the aggressor, this must mean a right to defend himself successfully! If lesser force is insufficient for effective defense, the use of the next greater force against the aggressor can not be denied to the defender.
In the chapter of The Ethics of Liberty dealing with self-defense Rothbard introduces the concept of proportionality, but it is clear that in this section of the chapter he is actually, somewhat confusingly, talking about punishment, not defense. In paragraphs fourteen through sixteen he does not use the word defense once, instead invoking punishment three times, once in the context of “the proportionality theory of punishment”.
Rothbard uses an example of a storekeeper who elects to shoot a bubblegum thief to illustrate the need for the punishment to “fit the crime”. That is a worthwhile principle where retribution is concerned, but means Rothbard omits to treat his example in the context of defense. In such a context Rothbard’s storekeeper would likely be equally out of bounds to shoot the bubblegum thief, but that is because it is extremely unlikely a shoplifter interested in a piece of bubble gum could be thwarted only if shot with a firearm.
A ‘lad’ who snatched a bubble gum would possibly give it up just if the storekeeper raised his finger, or pulled his ear. Consequentially to elect to shoot him instead would clearly be in excess of the least, sufficient force needed for the storekeeper to keep possession of his bubble gum. In any case a bubble gum is vehemently replaceable so there is no urgency to defense. The storekeeper has fair chances of being fully reimbursed for the bubble gum even should he let the thief escape the scene — possibly all he needs to do, for it to be so, is go and speak with the lad’s parents.
This does not mean that shooting the aggressor exceeds what may be justified by the necessity of defense in every instance of petty theft imaginable. Imagine a diabetic who needs to take regular insulin shots lest he dies of hyperglycemia. Now let us say he has been stranded somewhere without a reliable source of insulin, and a thief is unknowingly taking away with his last remaining supply. In this situation there is great urgency to defense. The aggressed-upon must thwart the aggressor momentarily or there may be severe consequences for him. Here the diabetic is within his rights to shoot the escaping thief if there is no other way for the sick man to stop the thief otherwise, eg if the thief is a faster runner, or will not heed calls to let go of the stolen property.
Both the principle of proportionality and the principle of the least, sufficient force place an upper limit on force that may be brought to bear against an aggressor. Either of these limitations may be greater than the other. There could be a criminal who was guilty of a series of heinous crimes, but who after a period on the run turned himself in of his own accord. Such a criminal could be punished severely, but no rough treatment of him could be justified by the right to defense as he was being taken into custody. On the other hand there could be a stubborn squatter who was relatively unobtrusive, but was nonetheless unwanted. The nature of his invasion of property could be very mild and so no great punishment could be demanded for him once he has been evicted. He could, however, be evicted in a seemingly harsh manner, if he through his own stubbornness made it impossible to defend against his presence with milder methods.
This is not trivial. A victim of crime could in the course of defense employ force that was in excess of what was required for a successful defense and not face legal trouble, if this force nonetheless did not exceed the level of force permitted by the right to retribution. However, this is only the case for the victim, but not for any of its agents acting on its behalf only in matters of defense. Also, such excess of force used in the course of defense will be subtracted from the force the victim may bring to bear against the aggressor in retribution for infringement of rights. An opposite scenario where a defense agent could employ force against the aggressor which was greater than the level of force prescribed by courts as appropriate punishment for the aggressor is likewise possible.
A case in point is the soldier of an occupation. The term for occupation carries eery, menacing connotations to it in many languages. Most of all in the languages of nations that have experienced it. Even the Americans who never did, but have occupied other nations, prefer to consume popular culture that condemns the occupier and strongly sides with the resistance against it, rather than the other way around. What is more the American president George W. Bush who personally planned and ordered the long and bloody occupation of Iraq (2003-2011) admitted he “wouldn’t be happy” if he himself were occupied.
We understand intuitively, that in the context of an occupation the occupier is the aggressor and that violent resistance to occupation is legitimate as well as commendable. There may be disagreement among human observes whether a particular real-life situation constitutes a foreign military occupation, but we are generally one in holding that if it does, then the occupied, in their bid to liberate themselves, have the right to take aim against any and all of the occupiers.
When watching a TV episode, of say Star Trek, featuring the French resistance ambushing a German patrol we do not ask ourselves whether the French made certain every one of the ambushed German soldiers had done something to warrant being killed as punishment — no, we understand intuitively, the French resistance are not acting to enact punishment on the German soldiers, but to defend their country from their presence. We should not be so naive as to believe even a comparatively mild occupation does not entail a series of grave violations against property, however, it is the case no matter what the sins of the occupation, an individual occupying soldier may be relatively innocent.
Seeing that for libertarians there is no such crime as “belonging to a criminal organization” the most some occupying soldiers, for example the recently-arrived replacements, may be guilty of is trespassing. Yet it is understood even such recently-arrived occupying troops are liable to be legitimately shot by the resistance. How is this just?
It is legitimate for the resistance to do so, because it is legitimate for the property owners whose land the occupiers disturb to demand the intruders evacuate at once. The former can be placed under no obligation to suffer the unwanted presence of the latter and to see their rights trampled by the invaders. Support for the resistance in this instance does not mean we believe occupying soldiers deserve to die as punishment for their trespassing, but merely that in such a scenario the property owners have the right to engage them with lethal force.
In a regular case of trespassing the defense agents of the property owner would be quite out of bounds to shoot a trespasser or plant explosive devices against him, because in all likelihood that would be well in excess of the force needed to be rid of the invader. In many cases all that would be needed would be to warn the trespassers they were on private property and they would walk away by themselves.
When the trespassers are instead the armed military personnel of a foreign state, however, such presumptions no longer apply. It is instead in all likelihood the case such intruders are so persistent and so able to withstand less lethal attempts at their removal to warrant ambushing them with great firepower. It is the occupying soldiers who by making themselves impervious to warnings, and to the use of less extreme means of defense while engaging in aggression, authorize the defenders to use ever greater force against them.
So it is the persistence of the aggressors, their determination to continue in their aggression and their ability to withstand less forceful attempts at bringing their violation of rights to an end, that warrants the use of greater force against them — not the nature of their transgression as such. Thus to defend themselves the aggressed-upon may not use force that is in excess of the least force that is still sufficient for a successful defense, but are justified in using any other amount. This principle, governing the use of force in defense against the aggressor, may be deemed the principle of the least, sufficient force.