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 no duties whatsoever. Second, there is the anticipated or discovered trespasser. To those parties, the landowner owes a duty of common humanity (See British Railways Board v. Herrington)- a duty to warn them of deadly conditions on the land which would be hidden to them, but of which the property owner is aware. A warning sign at the entrance to the land will suffice for this purpose. However, a property owner is under no duty to ascertain hazards on his own property, and cannot be held liable for failing to discover a deadly hazard which injures a trespasser.

Furthermore, a trespasser who is injured while on the Defendant\'s property cannot sue under a theory of strict liability, even if the landowner was engaged in ultrahazardous activities, such as the keeping of wild animals, or the use of explosives. Instead, the trespasser must prove that the property owner was negligent.

A property owner may use reasonable (nondeadly) force to prevent a person from trespassing on their land, or to expel a trespasser. However, a property owner may not force a trespasser off of his land if doing so would expose the trespasser to a risk of serious injury. For example, a trespasser who takes shelter in a stranger\'s barn during a powerful storm cannot be expelled until the storm is over.

Duty of Care