Private and Public Necessity Defense

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 What Is the Defense of Necessity?

There are certain situations in which people in emergencies have a partial or complete defense against a claim for civil or criminal trespass based on claims of private or public necessity. These defenses of necessity are only available if a person trespassed in order to avert an imminent threat of serious harm to themselves and/or others in the case of private necessity. The threat of harm must be other people only, or the public at large in the case of public necessity.

The exact definitions of the necessity defenses depend on the law of the state that applies in a particular civil or criminal case.

What Is Private Necessity?

Private necessity, also known as lesser harm, is a type of defense to allegations of both civil and criminal trespass onto the land of another. It is available to a perpetrator of trespass when the perpetrator commits trespass in order to prevent a greater harm even though the act done by the perpetrator is a crime, i.e., the crime of trespass.

So, in other words, it is a criminal defense available when a person commits criminal trespass to avoid the threat of greater harm. It is also a defense in a lawsuit involving a civil claim for trespass.

The elements of the private necessity defense are as follows:

  • The act of trespass was necessary to avoid a greater harm that threatened the perpetrator or others;
  • No more was done than was reasonably necessary to achieve the purpose of avoiding the greater harm;
  • The trespass itself did not create any risk of a greater harm or danger;
  • The perpetrator was not responsible for creating or contributing to the emergency that had to be avoided.

What Are Types of Private Necessity?

There are several types of situations that might qualify as private necessity. Two examples are as follows:

  • Avoidance of a Crime: A person might be running away from a potential robbery or other criminal offense and trespass on the land of another in the process;
  • Attempting to Save Self and Others: Perhaps a group of hikers is caught in a natural disaster of some kind, e.g., a severe storm. They knock on the door of a nearby cabin to ask for help, but there is no answer. They break into the cabin and enter and stay as long as necessary to escape the storm.
    • If charged with criminal trespass or sued by the owner of the cabin for civil trespass, the person would argue that they had to break into the cabin to save their own life and the lives of their fellow hikers.
    • They would further argue that there were no good alternatives and that the damage to the cabin was far less than the harm that they might have faced if they had not made the move they did.

It is important to keep in mind that in most states, the defendant in a criminal case has the burden of proving an affirmative defense. The degree of proof may be different in different states. The defendant may have to prove their defense by clear and convincing evidence or by a preponderance of the evidence. These are considered lower burdens than that of proof beyond a reasonable doubt.

Of course, the prosecution always has the burden of providing the guilt of a defendant beyond a reasonable doubt.

Likewise, in a civil case for trespass, the person who has been sued for trespass, also called the “defendant” in legal terminology, would have the burden of proving that they acted out of necessity, whether private or public.

The defenses of private and public necessity might also be available in cases that involve civil wrongs or criminal offenses other than trespass.

What Constitutes Necessity?

Necessity is a defense. It means that a person sued for a civil wrong or a criminal offense has a defense to liability. A private landowner would be unable to recover certain kinds of damages against a person whose action constitutes a necessity. If they suffered losses, however, they would be able to recover the damages to compensate for their losses.

For instance, if a private citizen trespasses on another person’s land, they could still be liable for damages such as breaking a window, damaging furniture, and the like.

In a criminal setting, the perpetrator or defendant would bear the burden of proving the necessary defense. Again, they would claim that the crime was committed under the following circumstances:

  • In an emergency;
  • In order to prevent significant bodily harm to the perpetrator or others;
  • The perpetrator did not create or contribute to creating the emergency.

What Is Public Necessity?

In tort law, public necessity is yet another defense that can be used against a claim of civil or criminal trespass. Public necessity is available to a person who interferes with another person’s property in an emergency situation to protect the community or society as a whole from a greater harm that would have happened if the person had not trespassed.

Public necessity may serve as an absolute defense, and a defendant might not be liable for any damages caused by their trespass. Exactly how effective the defense would be to a defendant for avoiding damages would be a matter of state law.

What Is Required to Assert Public Necessity?

There are generally three requirements for succeeding with the defense of public necessity as follows:

  • The individual believed that action was needed for the common good of others;
  • The belief must have been reasonable in light of the surrounding circumstances;
  • A public interest must have been involved.

The defense of public necessity might be especially useful to first responders or recovery workers in a civil emergency or natural disaster.

What Should I Do if My Property Is Damaged by a Trespasser?

A person on whose land another person has trespassed and caused damage would file a civil claim for damages against the person who committed the act of trespass.

If the person who sued the defendant is successful in claiming private or public necessity as a defense, it is likely to be only a partial defense to any claim for compensatory damages. The defendant who successfully argues their necessity defense may not have to pay for some or possibly even any of the damage they caused. This is usually more often true in cases of public necessity.

For private necessity cases, the defendant is probably still going to be liable for the damage they caused. They might, however, escape liability for punitive damages or nominal damages.

For example, in the case above, if a person’s cabin suffered physical damage, e.g., a broken window, the defendant might have to pay for the actual damage done when they broke into the cabin, but nothing more.

If the property owner or some third person were to claim non-economic losses, e.g., pain and suffering due to trespass in the cabin, the defendant might still be liable for those damages as well. For example, the owner might have been injured cleaning up the damage. Public policy might require that the trespasser pay for any medical expenses incurred by the owner.

Do I Need a Lawyer for Help With My Necessity Defense?

If you or a loved one needs help with necessity as a legal defense, you want to consult a criminal defense attorney. can connect you quickly to an experienced criminal defense attorney who can help protect your rights and guide you through the complex criminal justice system.

If you have been sued in a civil suit for civil trespass, you want to consult a personal injury lawyer. Again, can connect you to a lawyer who knows how to succeed with a defense in a civil case and can make sure your rights are fully protected.

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