At common law the owner of a dog or cat was not liable for its trespasses. Various reasons were assigned for this, such as the difficulty of keeping these animals under restraint, the slight ness of the damages ordinarily inflicted by their wanderings, and the common usage of allowing them greater liberty than that accorded to cattle. But if a dog, or eat, or other such animal he known by its owner to have vicious propensities, and, because of his failure properly to restrain it. it injure the person or property of another, he will be liable in damages.
There are some circumstances under which en try upon the land of another without his consent is jnstifiable or excusable, and so does not con stitute a trespass. Thus, if a public highway be so obstructed as to he impassable, a traveler may rightfully go around the obstruction upon the private land of an individual; and a person who, by virtue of a contract with another, has become the owner of personal property upon the latter's land, may enter and take it from such land; and again. when a vendor of personal property has rescinded the sale because of fraud practiced upon him. he may enter upon the land of the vendee, if not forbidden by the latter, and retake the property sold, and the same rule holds whenever an owner of land has wrongfully ac quired possession of the personalty of another and placed it upon his own land. It is general ly the rule, however, with these few exceptions, that a person who goes or sends upon the land of another, and takes his own chattels without per mission of such land-owner, however such chat tels may have come to he there, is guilty of a trespass. If a trespass be attempted upon real property, or upon personal property which is in the actual possession of its owner, the person rightfully in possession of the same may proper ly use all the force that is necessary to prevent the commission of the wrong. But if he employ more force than is actually needed to repel the violence of the intruder, lie makes himself liable to an action for assault and battery, and his aet may constitute a crime. Crowing out of this
right to make use of so much violence as is requisite to prevent intrusion is the well-known common-law maxim that "A man's house is his castle." Yet there are a few cases in which even the privacy of a person's dwelling-house may be invaded without his permission. An officer of the law, when executing criminal process—as in seek ing to apprehend a criminal or one charged with a crime—may use the needed force to enter a building in which such person is secreted. And even in the execution of civil process an officer may break open inner doors after he has peace ably obtained entrance into the house; but no civil process can authorize him to employ force or violence to obtain ingress through the outer door of a dwelling. There are, moreover, many circumstances under which persons are invited. by implication, to go upon the property of others and so do not become trespassers, if. not being expressly forbidden to do so, they so enter, Thus, it is ordinarily no act of trespass for a person to enter the house of his neighbor upon matters of business or to make a social call: so keepers of stores, theatres, hotels_ete., hold out to the public a general invitation to enter neon their properties for the purpose of dealing with them. But even in such eases those who enter or remain against the express prohibition of the owner or proprietor become trespassers in so doing. If one go upon the property of another rightfully, but abuse or make ill use of the privilege or au thority under which he entered, as if go into a tavern or theatre and refuse to leave within a reasonable time or when ordered to do so, he thereby becomes a trespasser al, initio, or from the time when he entered.
Consult: Pollock and Maitland, History of English Lan' (2(1 ed.. Boston. 1899) : Pomeroy, Remedies and Remedial Rights (Boston, 1883) ; Pollock, The Law of Torts (London and New York, 1901).