12.—: Private defence.

Self-defence. Self-defence (or rather private defence, for defence of one’s self is not the only case) is another ground of immunity well known to the law. To repel force by force is the common instinct of every creature that has means of defence. And when the original force is unlawful, this natural right or power of man is allowed, nay approved, by the law. Sudden and strong resistance to unrighteous attack is not merely a thing to be tolerated; in many cases it is a moral duty. Therefore it would be a grave mistake to regard self-defence as a necessary evil suffered by the law because of the hardness of men’s hearts. The right is a just and perfect one. It extends not only to the defence of a man’s own person, but to the defence of his property or possession. And what may be lawfully done for oneself in this regard may likewise be done for a wife or husband, a parent or child, a master or servant. At the same time no right is to be abused or made the cloak of wrong, and this right is one easily abused. The law sets bounds to it by the rule that the force employed must not be out of proportion to the apparent urgency of the occasion. We say apparent, for a man cannot be held to form a precise judgment under such conditions. The person acting on the defensive is entitled to use as much force as he reasonably believes to be necessary. Thus it is not justifiable to use a deadly weapon to repel a push or a blow with the hand. It is even said that a man attacked with a deadly weapon must retreat as far as he safely can before he is justified in defending himself by like means. But this probably applies (so far as it is the law) only to criminal liability. On the other hand if a man presents a pistol at my head and threatens to shoot me, peradventure the pistol is not loaded or is not in working order, but I shall do no wrong before the law by acting on the supposition that it is really loaded and capable of shooting. “Honest and reasonable belief of immediate danger” is enough.

Killing of animals in defence of property. Cases have arisen on the killing of animals in defence of one’s property. Here, as elsewhere, the test is whether the party’s act was such as he might reasonably, in the circumstances, think necessary for the prevention of harm which he was not bound to suffer. Not very long ago the subject was elaborately discussed in New Hampshire, and all or nearly all the authorities, English and American, reviewed. Some of these, such as Deane v. Clayton, turn less on what amount of force is reasonable in itself than on the question whether a man is bound, as against the owners of animals which come on his land otherwise than as of right, to abstain from making the land dangerous for them to come on. And in this point of view it is immaterial whether a man keeps up a certain state of things on his own land for the purpose of defending his property or for any other purpose which is not actually unlawful.

As to injuries received by an innocent third person from an act done in self-defence, they must be dealt with on the same principle as accidental harm proceeding from any other act lawful in itself. It has to be considered, however, that a man repelling imminent danger cannot be expected to use as much care as he would if he had time to act deliberately.

Assertion of rights distinguished from self-defence. Self-defence does not include the active assertion of a disputed right against an attempt to obstruct its exercise. I am not justified in shooting, or offering to shoot, one who obstructs my right of way, though I may not be able to pass him otherwise, and though I am justified in resisting, within due bounds, any active force used on his part. It seems the better opinion “that the use of force which inflicts or may inflict grievous bodily harm or death—of what in short may be called extreme force—is justifiable only for the purpose of strict self-defence”. I may be justified in pushing past the obstructor, but this is not an act of self-defence at all; it is the pure and simple exercise of my right itself.

Many interesting questions, in part not yet settled, may be raised in this connexion, but their interest belongs for most practical intents to public and not to private law. It must not be assumed, of course, that whatever is a sufficient justification or excuse in a criminal prosecution will equally suffice in a civil action.

Injury to third persons from acts of self-defence. Some of the dicta in the well-known case of Scott v. Shepherd go the length of suggesting that a man acting on the spur of the moment under “compulsive necessity” (the expression of De Grey C.J.) is excusable as not being a voluntary agent, and is therefore not bound to take any care at all. But this appears very doubtful. In that case it is hard to believe that Willis or Ryal, if he had been worth suing and had been sued, could have successfully made such a defence. They “had . . . . . a right to protect themselves by removing the squib, but should have taken care”—at any rate such care as was practicable under the circumstances—“to do it in such a manner as not to endamage others”. The Roman lawyers held that a man who throws a stone in self-defence is not excused if the stone by misadventure strikes a person other than the assailant. Perhaps this is a harsh opinion, but it seems better, if the choice must be made, than holding that one may with impunity throw a lighted squib across a market-house full of people in order to save a stall of gingerbread. At all events a man cannot justify doing for the protection of his own property a deliberate act whose evident tendency is to cause, and which does cause, damage to the property of an innocent neighbour. Thus if flood water has come on my land by no fault of my own, this does not entitle me to let it off by means which in the natural order of things cause it to flood an adjoining owner’s land.