MBE Rules · Torts

Necessity

Vincent v. Lake Erie

The rule

Private necessity is an incomplete privilege — entry to avoid greater harm is protected from trespass liability, but the entrant pays for actual damage; public necessity is a complete defense.

In plain English

The rule of necessity allows a person to enter another's property to prevent a greater harm. In cases of private necessity, while the person is protected from trespass claims, they must compensate the property owner for any actual damage caused. In contrast, public necessity provides a complete defense against liability for trespass.

Worked example

A homeowner finds that a fire is spreading from a neighbor's property and threatens to engulf their house. To prevent the fire from spreading further, the homeowner enters the neighbor's yard and uses a hose to douse the flames. While the homeowner is protected from trespass liability due to public necessity, they must pay for any damage caused to the neighbor's property in the process.

Memory hook

Private necessity protects you, but you still pay the price!

The trap

Exams may present scenarios where students confuse private necessity with public necessity, leading them to overlook the requirement to pay for damages in private cases. Be careful not to assume complete immunity from liability in private necessity situations.

How examiners test it

Questions often involve fact patterns where a person enters property to prevent harm, requiring students to distinguish between private and public necessity and assess liability for damages.

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