Describe a trespass to land. What must the property owner show? What are the property owner's duties and remedies? What are some defenses against trespass to land?

A trespass to land occurs whenever a person, without permission, enters onto land that is owned by another, causes anything to enter onto the land, remains on the land, or permits anything to remain on it. Actual harm to the land is not an essential element of this tort because the tort is designed to protect the right of owners to exclusively possess their property. Common trespasses include walking or driving on the land, shooting a gun over the land, throwing rocks at a building that belongs to someone else, causing water to back up on someone else's land, and placing part of one's building on an adjoining landowner's property.
The owner of the real property must show that a person is a trespasser. For example, a person who ignores "private property" signs and enters, uninvited, onto the property is clearly a trespasser. A guest in your home is legally an invitee, not a trespasser-unless she has been asked to leave but refuses. Any person who enters onto your property to commit an illegal act (such as a thief) is a trespasser, without posted signs.
Normally, a trespasser must pay for any damage caused to the property and can be removed from the premises through the use of reasonable force without the owner's being liable for assault and battery. Further, a property owner owes no duty of care to a trespasser.
If a trespasser sneaks across your backyard and breaks a leg when he steps in a hole in your lawn, he cannot sue you for having a hole in the lawn.
The most common defense to trespass is that the trespass was justified. For example, when a trespasser enters to assist someone in danger, a defense exists. Another defense exists when the trespasser can show that he or she had permission to come onto the land for a specified purpose, such as to read an electric meter. Note that the property owner can revoke such permission. If the property owner asks a meter reader to leave and the meter reader refuses, the meter reader at that point becomes a trespasser.