Necessity as a defence

By Anu Mittal, Symbiosis Law School, Noida

Editor’s note: The law of torts, with a few exceptions, acknowledges necessity as a defence. It recognizes that there may be situations of such overwhelming urgency that a person must be allowed to respond by breaking the law. It is defined under § 81 of the IPC. This paper analyses the factors involved in pleading this defence and the burden of proof that must be met. It also analyses the two types of necessity – public and private, and its importance in law.


What is the necessity defense exactly and how and under what circumstances might it work in law of tort? As in the case of Baender v Barnett a fire broke out in a maximum security prison, and the prisoners, threatened by death, break out of their cells. Surely they are not guilty of the crime of escape? Here’s a situation where most of us would agree that necessity could be a defense and that the prisoners who broke out of their cells “out of necessity” ought not to be convicted for escape[1]. The defense of necessity recognizes that there may be situations of such overwhelming urgency that a person must be allowed to respond by breaking the law. Necessity is based on maxim salus populi suprema lex, i.e. ‘the welfare of the people is the supreme law’. Necessity typically involves a defendant arguing that he committed the crime in order to avoid a greater evil created by natural forces. Necessity as a justification (warranted or encouraged conduct where the defendant is found not culpable). Necessity is an affirmative defense that a defendant invokes the defense against the torts of trespass to chattels, trespass to land or conversion. The early trial which took place was Regina v. Dudley and Stephens (1884) 14 QBD 273 DC[2].

Meaning and Definition

Necessity as a defense is defined under section 81 in Indian Penal Code as:

“Act likely to cause harm, but done without criminal intent, and to prevent other harm.—Nothing is an offence merely by reason of its being done with the knowledge that it is likely to cause harm, if it be done without any criminal intention to cause harm, and in good faith for the purpose of preventing or avoiding other harm to person or property.”

Factors affecting necessity

Affirmative defense

A defendant typically invokes the defense

Against intentional torts of trespass to chattels, , trespass to land or conversion.

With the necessity defense there will always be a prima facie violation of the law.

A tort is a civil wrong for which unliquidated damages have to be compensated by the defendant even if he did in case of necessity. The defense of necessity is only applicable when the defendant is able to justify his unlawful acts. It seems to be generally assumed that, if the defense of necessity succeeds, that is the end of the matter.

To present the defense at trial, defendants must need to meet the burden of provision of the four elements:

They were forced with a choice of evils and choose the lesser evil.

They acted to prevent imminent harm

They reasonably anticipated a direct casual relationship between their conduct and the harm to be averted.

And, they had no legal alternatives to violating the law.[3]

These elements suggests that defense to the liability for unlawful activity where the conduct cannot be avoided and one is justified in the particular conduct because it will prevent the occurrence of a harm that is more serious.

Historically the principle has been seen to be restricted to two groups of cases, which have been called cases of public necessity and cases of private necessity. The act of plaintiff distinguishes the necessity of defense with other defenses.  But the better view is that necessity should be used by defendants who rationally chose an illegal course of action that is the lesser of two evils.

Types of necessity

Public Necessity

Public necessity pertains to action taken by public authorities or private individuals to avert a public calamity. The action consists in destroying or appropriating another’s property.[4] The classic example of public necessity is the destruction of private property to prevent the spread of fire [5]or disease [6]and hence to avert an injury to the public at large. Public necessity is in operational where the police trespass on damage. Private property in order to apprehend a criminal suspect or gain access to the site of an emergency[7].  The principle behind public necessity is that the law regards the welfare of the public as superior to the interest of individuals and when there is a conflict between the latter must give way[8]. Public necessity serves as an absolute defense. The first case which was filled with reference to public necessity was Surocco v Geary.[9]

With this illustration public necessity is being defined.  “A ship which had run into difficulties found it necessary to discharge her cargo of oil, thereby polluting beaches which belong to the plaintiff. Since the discharge of the oil was necessary to save the crew, and not only the ship, it was accepted that the defense of necessity applied.

Private Necessity

Private necessity arises from self interest rather than from a community at large. It takes place when the defendant wants to protect his own interest. It does not serve as an absolute defense unlike in the case of public necessity. Private necessity can be explained with the following example. If defendant entered upon his neighbor’s land without his consent, in order to prevent the spread of fire into his own land. The principle applied for private necessity is “necessitas inducit privilegium quod jura private”, meaning ‘Necessity induces a privilege because of a private right’. This maxim makes it clear that private defense its more kind of a privilege enjoyed by many person. The earliest case of private defense was Vincent v. Lake Erie Transp. Co.

There is, however, a third group of case, which is also properly described as founded upon the principle of necessity and which is more pertinent. These cases are concerned with action taken as a matter of necessity to assist another person without his consent. To give a simple example, a man who seizes another and forcibly drags him from the path of an oncoming vehicle, thereby saving him from injury or even death, commits no wrong.

These are concerned not only with the preservation of the life or health of the assisted person, but also with the preservation of his property (sometimes an animal, sometimes an ordinary chattel) and even with certain conduct on his behalf in the administration of his affairs.”

Importance of Necessity

Necessity incorporates flexibility into laws that would have been lead to unjust results (that is, punishment of desirable conduct) if applied mechanically[10]. The defence of necessity applies to situations where torture is morally justified. Like in the case of a prisoner who breaks the prison and runs away because he was mentally and physically tortured by the prison authorities. Necessity provides relief in situation pertaining to this. Necessity” defense has the effect of allowing one who acts under the circumstances of ‘necessity’ to escape criminal liability. Perhaps the necessity defense should be thought of as a moral provision for mala in se offenses.  Mala in se offenses generally protect against harms to others, and to the extent that the necessity defense defines situations in which one may harm others. The shape of the defense should track our moral judgments about when it is morally permissible for a person to harm others.

Limiting the Necessity Defense

Necessity defense restricts the ways in which private citizens may use force that harms another’s interest, the limited scope of the necessity defense is one of many tools that help sustain the state’s monopoly on legitimate violence exists to empower individuals where individuals are supposed to be powerless; it cannot be used to confer powers on the state as well. Most importantly it entirely depends appropriately for a government body to examine what is allowed under the necessity defense and seek guidance as to what it is allowed to do. After all, the government’s power is greater than what is allowed to private individuals under the necessity defense, and the greater state’s monopoly on violence must necessarily include the lesser individual’s use of violence. The necessity defense can be asserted only when compatible with the particular federal crime at issue[11].

How necessity defense looked up by courts?

If a court determined that a given offense was regulatory in nature, the statute authorizes a necessity defense. If none were present, the defense would not be allowed[12]. The necessity defense, by its nature, challenges and undermines that the given situation needed to choose from the two evils. It carries the implication that violation of a given rule is positively desirable, thus turning it in to a standard. Common law necessity requires that the harm be truly imminent. The allowing defendants to use the necessity defense in regulatory cases will tend to distract courts from the employment of other common law defenses. The cases where courts have expressly ruled on the necessity defense’s availability, either on the facts or as a matter of law, can be roughly divided into three main categories: a court may (1) grant a jury instruction on necessity and allow the defendant to present evidence concerning it; (2) find the defense incompatible with the offense involved; or (3) find that the defendant failed to meet his burden of production on at least one element of the defense.

Trespass to Chattels, Land or conversion

With the necessity defense there will always be a prima facie violation of the law. The violation will consist of trespass, conversion or other kinds of infringement of property rights. Under the necessity doctrine, there is a weighing of interests: the act of invasion of another’s property is justified under the necessity doctrine only if done to protect or advance some private or public interest of a value greater than, or at least equal to, that of the interest invaded. A major issue associated with both private and public necessity is whether compensation is owed to the aggrieved party whose property is damaged, appropriated or destroyed. There is a general sense in the doctrine of necessity that one has the qualified privilege to intentionally trespass onto the land of another in order to prevent serious harm to oneself, to one’s own land, to one’s chattels, or to the person, land, or chattels of another. However, compensation must ordinarily be paid for any harm done in the process. The Comment to this section states that when necessary to prevent serious harm, a person is privileged “to break and enter or to destroy a fence or other enclosure and indeed a building, including a dwelling only when the defendant’s action are reasonable.


The conclusion that one can reach is that necessity considers circumstantial morality and provides one to be saved from his circumstantial offence. Necessity else than been a new defence is also an evolving concept, which one can see through the Vincent case and as well as R v. Dudley and Stephens case, which cleared some essentials regarding it. The way it will evolve will depend on, how the judiciary interprets it in future cases. There is no doubt that, it has attracted some critical criticism and which also do make some sense as it was in obiter dicta in R v. Dudley and Stephens, where it was said not every necessity can be ground for necessity otherwise, there will be utter chaos and nothing else, this inference of the judge seems very true.

Edited by Neerja Gurnani

[1] Baender v Barnett, 255 US 224 (1921).

[2] Regina v. Dudley and stephens (1884) 14 QBD 273 DC[2].

[3] Schoon, 971 F2d at 195, citing United States v Aguilar, 883 F2d 662, 693 (9th Cir 1989).

[4] BLACK’S LAW DICTIONARY 1059 (8th ed. 2004) (defining public necessity); see also

Surocco v. Geary, 3 Cal. 69 (Cal. 1853)

[5] RESTATEMENT (SECOND) OF TORTS § 204 (Entry to Arrest for Criminal Offense), RESTATEMENT (SECOND) OF TORTS § 196 (Public Necessity).

[6] Surocco, 3 Cal. at 71; Conwell v. Emrie, 2 Ind. 35, 35 (1850); Field v. City of Des Moines, 39 Ia. 575, 575 (1874)

[7] . Seavy v. Preble, 64 Me. l20 (l874).

[8]  United States v. Schoon, 971 F.2d 193, 196

[9] (1853) (1853), 3 Cal 69, 58 Am Dec 385 (Cal SC)

[10] Alan M. Dershowitz, Is It Necessary to Apply “Physical Pressure”

[11] Oakland Cannabis, 532 US at 491 (“The [necessity] defense cannot succeed when the legislature itself has made a ‘determination of values.’”).

[12] United States v Oakland Cannabis Buyers’ Cooperative

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