I need not recur to the possible historical connection of either of these last forms of liability with the noxoe deditio, because, whether that origin is made out or not, the policy of the rule has been accepted as sound, and carried further in England within the last few years by the doctrine that a man who brings upon his land and keeps there anything likely to do mischief if it escape, must keep it in at his peril. The strictness of this principle will vary in different jurisdictions, as the balance varies between the advantages to the public and the dangers to individuals from the conduct in question.Danger of harm to others is not the only thing to be considered, as has been said already.The law allows some harms to be intentionally inflicted, and a fortiori some risks to be intentionally run.In some Western States a man is not required to keep his cattle fenced in.Some courts have refused to follow Rylands v.Fletcher. On the other hand, the principle has been applied to artificial reservoirs of water, to cesspools, to accumulations of snow and ice upon a building by reason of the form of its roof, and to party walls. In these cases, as in that of ferocious animals, it is no excuse that the defendant did not know, and could not have found out, the weak point from which the dangerous object escaped.The period of choice was further back, and, although he was not to blame, he was bound at his peril to know that the object was a continual threat to his neighbors, and that is enough to throw the risk of the business on him.
I now pass to cases one degree more complex than those so far considered.In these there must be another concomitant circumstance known to the party in addition to those of which the knowledge is necessarily or practically proved by his conduct.
The cases which naturally suggest themselves again concern animals.Experience as interpreted by the English law has shown that dogs, rams, and bulls are in general of a tame and mild nature, and that, if any one of them does by chance exhibit a tendency to bite, butt, or gore, it is an exceptional phenomenon.
Hence it is not the law that a man keeps dogs, rams, bulls, and other like tame animals at his peril as to the personal damages which they may inflict, unless he knows or has notice that the particular animal kept by him has the abnormal tendency which they do sometimes show.The law has, however, been brought a little nearer to actual experience by statute in many jurisdictions.
Now let us go one step farther still.A man keeps an unbroken and unruly horse, knowing it to be so.That is not enough to throw the risk of its behavior on him.The tendency of the known wildness is not dangerous generally, but only under particular circumstances.Add to keeping, the attempt to break the horse;still no danger to the public is disclosed.But if the place where the owner tries to break it is a crowded thoroughfare, the owner knows an additional circumstance which, according to common experience, makes this conduct dangerous, and therefore must take the risk of what harm may be done. On the other hand, if a man who was a good rider bought a horse with no appearance of vice and mounted it to ride home, there would be no such apparent danger as to make him answerable if the horse became unruly and did damage. Experience has measured the probabilities and draws the line between the two cases.
Whatever may be the true explanation of the rule applied to keeping tigers, or the principle of Rylands v.Fletcher, in the last cases we have entered the sphere of negligence, and, if we take a case lying somewhere between the two just stated, and add somewhat to the complexity of the circumstances, we shall find that both conduct and standard would probably be left without much discrimination to the jury, on the broad issue whether the defendant had acted as a prudent man would have done under the circumstances.
As to wrongs called malicious or intentional it is not necessary to mention the different classes a second time, and to find them a place in this series.As has been seen, they vary in the number of circumstances which must be known.Slander is conduct which is very generally at the risk of the speaker, because, as charges of the kind with which it deals are manifestly detrimental, the questions which practically arise for the most part concern the defence of truth or privilege.Deceit requires more, but still simple facts.Statements do not threaten the harm in question unless they are made under such circumstances as to naturally lead to action, and are made on insufficient grounds.
It is not, however, without significance, that certain wrongs are described in language importing intent.The harm in such cases is most frequently done intentionally, if intent to cause a certain harm is shown, there need to prove knowledge of facts which made it that harm would follow.Moreover, it is often much easier to prove intent directly, than to prove the knowledge which would make it unnecessary.
The cases in which a man is treated as the responsible cause of a given harm, on the one hand, extend beyond those in which his conduct was chosen in actual contemplation of that result, and in which, therefore, he may be to have chosen to cause that harm;and, on the other hand, they do not extend to all instances where the damages would not have happened but for some remote election his part.Generally speaking, the choice will be found to have extended further than a simple act, and to co-ordinated acts into conduct.Very commonly it will have extended further still, to some external consequence.But generally, also, it will be found to have stopped short of the consequence complained of.
