Trespasser

In the law of tort, property, and criminal law a trespasser is a person who commits the act of trespassing on a property, that is, without the permission of the owner. Being present on land as a trespasser thereto creates liability in the trespasser, so long as the trespass is intentional. At the same time, the status of a visitor as a trespasser (as opposed to an invitee or a licensee) defines the legal rights of the visitor if they are injured due to the negligence of the property owner.

The tort of trespass to land requires an intentional physical invasion of the plaintiff's real property by the defendant or a refusal to leave when ordered to leave.

For example, a person walking in a public park who trips and rolls down a hill will not be liable for trespass just because the bottom of the hill is on private land.

The trespasser need not enter the land in person. Indeed, if A and B are standing next to C's land, and A pushes B onto the land without entering it himself, it is A (and not B, who did not intend to enter that space) who is liable for the trespass to C's land. There must be some physical entry, however. Causing noise, light, odors, or smoke to enter the land of another is not a trespass, but is instead a different tort, nuisance.

For purposes of determining liability, the landowner's property rights extend above and below the land to as much distance as the landowner can beneficially use. Even a low-flying plane can trespass if it enters this usable space.

A constructive trespass occurs when a person who has permission to be on the land overstays their welcome. A person who stays in a business after its closing time, or who goes to a dinner party but refuses to leave long after the other guests have gone home, is a trespasser despite his initially proper presence. Furthermore, a guest's status as a trespasser arises as soon as he resists when the property owner tells him to leave the property. This is not a constructive trespass if the guest is unconscious.

With respect to the duties owed to trespassers, there are two types of trespassers to consider. First, there is the undiscovered trespasser, to whom the property owner owes only a duty not to "trap" or wilfully harm the trespasser. At the outset, the concept of traps was narrowly defined. More recently, courts have engaged in some creativity, adopting a broader interpretation of a trap.

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