Intentional torts - Necessity

Learning Outcomes

After reading this article, you will be able to explain the necessity defense in intentional torts, distinguish between public and private necessity, identify when necessity excuses liability for property damage, and apply these rules to MBE-style scenarios. You will also recognize common exam pitfalls and the precise requirements for necessity to operate as a defense.

MBE Syllabus

For MBE, you are required to understand the necessity defense as it applies to intentional torts. This includes knowing the difference between public and private necessity, the scope of protection each provides, and the consequences for property damage. You should be able to:

• Define necessity as a defense to intentional torts involving property.
• Distinguish between public necessity (complete defense) and private necessity (qualified defense).
• Identify when necessity excuses liability for trespass or conversion.
• Recognize when compensation for property damage is required.
• Apply necessity principles to fact patterns involving emergencies or threats to persons or property.

Test Your Knowledge

Attempt these questions before reading this article. If you find some difficult or cannot remember the answers, remember to look more closely at that area during your revision.

1. Which of the following best describes the defense of public necessity?
   1. It is available only to government officials.
   2. It is a complete defense to intentional torts involving property when the act protects the public from imminent harm.
   3. It excuses liability for personal injury but not property damage.
   4. It applies only to trespass to land, not to chattels.
2. In which situation is a person who enters another’s property to protect their own property from harm still liable for actual damage caused?
   1. Public necessity.
   2. Private necessity.
   3. Consent.
   4. Self-defense.
3. Which of the following is true regarding private necessity?
   1. It is a complete defense to all intentional torts.
   2. It excuses all liability for property damage.
   3. It allows entry but requires payment for actual harm caused.
   4. It applies only to government actors.

Introduction

Necessity is a defense to certain intentional torts involving property, such as trespass to land, trespass to chattels, and conversion. It arises when a person intentionally interferes with another’s property to prevent a greater harm. The law recognizes two types of necessity: public and private. The scope of the defense and the consequences for property damage differ depending on which type applies.

Key Term: Necessity A defense to intentional torts involving property, where the defendant acts to prevent a threatened harm, either to the public or to themselves or their property.

Types of Necessity

Necessity is divided into public necessity and private necessity. The distinction is critical for the MBE, as it determines whether the defendant is liable for property damage.

Public Necessity

Public necessity arises when a person (including private citizens) intentionally interferes with property to prevent a threat to the community or a significant group. The act must be reasonably necessary to avert an imminent public disaster, such as fire, flood, or disease.

Key Term: Public Necessity A defense to intentional property torts where the defendant acts to protect the public from imminent harm; it is a complete defense, excusing all liability.

Private Necessity

Private necessity occurs when a person intentionally interferes with property to protect their own interests or those of a limited number of people. The act must be reasonably necessary to prevent serious harm to the actor, their property, or a small group.

Key Term: Private Necessity A defense to intentional property torts where the defendant acts to protect their own or a few persons’ interests; it is a qualified defense, excusing liability for the trespass but not for actual property damage.

Scope of the Defense

Public Necessity—Complete Defense

If public necessity applies, the defendant is not liable for the trespass or for any resulting property damage, even if the property owner suffers a loss. This rule encourages decisive action to prevent widespread harm.

Private Necessity—Qualified Defense

If private necessity applies, the defendant is not liable for the trespass itself but must pay for any actual damage caused to the property. The property owner cannot exclude the defendant while the necessity continues, but compensation is required for losses.

Worked Example 1.1

A firefighter, acting without a warrant, demolishes a homeowner’s fence to create a firebreak and stop a rapidly spreading wildfire threatening the town. The homeowner sues for trespass and property damage. Is the firefighter liable?

Answer: No. This is public necessity. The firefighter acted reasonably to protect the public from imminent harm. Public necessity is a complete defense, so there is no liability for the trespass or the property damage.

Worked Example 1.2

During a severe storm, a boater ties their vessel to a private dock to avoid sinking. The boat survives, but the dock is damaged. The dock owner sues for trespass and damage. Is the boater liable?

Answer: The boater has a defense of private necessity. They are not liable for the trespass, but they must pay for the actual damage to the dock.

Exam Warning

On the MBE, do not confuse public necessity (complete defense, no liability for damage) with private necessity (qualified defense, must pay for actual harm). Carefully read the facts to determine whose interests are being protected.

Revision Tip

If the act protects the public, necessity is a complete defense. If it protects only the actor or a few, necessity excuses the trespass but not property damage.

Key Point Checklist

This article has covered the following key knowledge points:

• Necessity is a defense to intentional torts involving property.
• Public necessity is a complete defense; no liability for trespass or property damage.
• Private necessity is a qualified defense; no liability for trespass, but compensation required for actual damage.
• Public necessity protects actions taken to avert imminent harm to the community.
• Private necessity protects actions taken to prevent harm to oneself or a small group.
• The property owner cannot exclude someone acting under private necessity while the necessity continues.
• Necessity does not apply to intentional torts against persons (e.g., battery).

Key Terms and Concepts

• Necessity
• Public Necessity
• Private Necessity