There is, however, an important consideration, which has not yet been adverted to.It is undoubtedly possible that those who have the making of the law should deem it "wise to put the mark higher in some cases than the point established by common practice at which blameworthiness begins.For instance, in Morris v.Platt, the court, while declaring in the strongest terms that, in general, negligence is the foundation of liability for accidental trespasses, nevertheless hints that, if a decision of the point were necessary, it might hold a defendant to a stricter rule where the damage was caused by a pistol, in view of the danger to the public of the growing habit of carrying deadly weapons.Again, it might well seem that to enter a man's house for the purpose of carrying a present, or inquiring after his health when he was ill, was a harmless and rather praiseworthy act, although crossing the owner's boundary was intentional.It is not supposed that an action would lie at the present day for such a cause, unless the defendant had been forbidden the house.
Yet in the time of Henry VIII.it was said to be actionable if without license, "for then under that color my enemy might be in my house and kill me." There is a clear case where public policy establishes a standard of overt acts without regard to fault in any sense.In like manner, policy established exceptions to the general prohibition against entering another's premises, as in the instance put by Chief Justice Choke in the Year Book, of a tree being blown over upon them, or when the highway became impassable, or for the purpose of keeping the peace. Another example may perhaps be found in the shape which has been given in modern times to the liability for animals, and in the derivative principle of Rylands v.Fletcher, that when a person brings on his lands, and collects and keeps there, anything likely to do mischief if it escapes, he must keep it in at his peril; and, if he does not do so, is prima facie answerable for all the damage which is the natural consequence of its escape.Cases of this sort do not stand on the notion that it is wrong to keep cattle, or to have a reservoir of water, as might have been thought with more plausibility when fierce and useless animals only were in question. It may even be very much for the public good that the dangerous accumulation should be made (a consideration which might influence the decision in some instances, and differently in different jurisdictions); but as there is a limit to the nicety of inquiry which is possible in a trial, it may be considered that the safest way to secure care is to throw the risk upon the person who decides what precautions shall be taken.The liability for trespasses of cattle seems to lie on the boundary line between rules based on policy irrespective of fault, and requirements intended to formulate the conduct of a prudent man.
It has been shown in the first Lecture how this liability for cattle arose in the early law, and how far the influence of early notions might be traced in the law of today, Subject to what is there said, it is evident that the early discussions turn on the general consideration whether the owner is or is not to blame.
But they do not stop there: they go on to take practical distinctions, based on common experience.Thus, when the defendant chased sheep out of his land with a dog, and as soon as the sheep were out called in his dog, but the dog pursued them into adjoining land, the chasing of the sheep beyond the defendant's line was held no trespass, because "the nature of a dog is such that he cannot be ruled suddenly." It was lawful in ploughing to turn the horses on adjoining land, and if while so turning the beasts took a mouthful of grass, or subverted the soil with the plough, against the will of the driver, he had a good justification, because the law will recognize that a man cannot at every instant govern his cattle as he will. So it was said that, if a man be driving cattle through a town, and one of them goes into another man's house, and he follows him, trespass does not lie for this. So it was said by Doderidge, J., in the same case, that if deer come into my land out of the forest, and I chase them with dogs, it is excuse enough for me to wind my horn to recall the dogs, because by this the warden of the forest has notice that a deer is being chased. The very case of Mason v.Keeling, which is referred to in the first Lecture for its echo of primitive notions, shows that the working rules of the law had long been founded on good sense.
With regard to animals not then treated as property, which in the main were the wilder animals, the law was settled that, "if they are of a tame nature, there must be notice of the ill quality;and the law takes notice, that a dog is not of a fierce nature, but rather the contrary." If the animals "are such as are naturally mischievous in their kind, he shall answer for hurt done by them, without any notice." The latter principle has been applied to the case of a bear, and amply accounts for the liability of the owner of such animals as horses and oxen in respect of trespasses upon land, although, as has been seen, it was at one time thought to stand upon his ownership.It is said to be the universal nature of cattle to stray, and, when straying in cultivated land, to do damage by trampling down and eating the crops, whereas a dog does no harm.It is also said to be usual and easy to restrain them. If, as has been suggested, the historical origin of the rule was different, it does not matter.
