Justification: Necessity

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The nature and domain of necessity

The prohibitions of criminal law apply in "normal" situations. The various criminal defenses delineate situations that are, in relevant ways, exceptional. Persons may not kill, but the defense of self-defense makes clear that they may do so in the exceptional circumstance of being threatened with deadly force. Similarly, one may commit harm with legal impunity if under the influence of a serious, credible, and imminent physical threat, that is, if one acts under duress. The defense of necessity alludes to exceptional circumstances in which compliance with the law is likely to involve greater harm to persons or property than would violating it.

For example, running a stop light may be justified when the passenger in one's car has a medical emergency for which every second counts. A hiker lost in the woods in a sudden ice storm or impending avalanche may seek shelter and trespass in an empty house to save her life. Or an individual fighting a forest fire may have to seize and destroy private property to create a firebreak and prevent still greater damage. In each of these situations, the defense of necessity is available to justify harmful actions when the actor deliberately chooses the lesser evil. The notion of necessity does not, as the term might imply, refer to the absence of choice, the implication that one's actions were necessitated and not freely willed. Rather it implies the actor was appropriately concerned to minimize harm, and in that sense engaged in the kind of conduct that law may reasonably encourage.

Certain limits follow from this understanding of the defense of necessity. The harm-causing violation of a legal prohibition must be the least harmful alternative. It is not available if the actor is aware of other options that would further minimize the breach. By the same token, the actor is not fully exculpated if he creates the situation of choice-of-evils out of negligence. The driver who knowingly uses a car with defective brakes will remain criminally liable for his reckless damage when he swerves to avoid a pedestrian and runs into a shop window. On the other hand, the actor who chooses the apparent lesser evil out of a reasonable good faith misunderstanding may nonetheless claim necessity. He may, for example, interrupt two actors rehearsing the assassination scene from Julius Caesar by assaulting the actor playing Brutus in the false belief that the threatened stabbing is a genuine attack.

Many recent cases have tested the limits of the necessity defense. So-called pro-life abortion protestors have invoked it as a defense for trespass on the private grounds of abortion clinics and even for killing doctors and nurses (Wichita v. Tilson, 855 P2d. 911 (1993)). Necessity has been claimed in euthanasia cases; defendants have argued that the perpetuation of suffering in the face of inevitable death is the greater evil (for example, Gilbert v. State, 487 So.2d. 1185 (1986)). Necessity is also arguably relevant as a defense for persons accused of dispensing such prohibited drugs as marijuana for medical purposes (State v. Tate, 505 A2d. 941 (1986)). And, for at least four decades, civil disobedients have argued that their violations of law are justified by their cause, whether it is nuclear disarmament, an "immoral" war, or the preservation of the environment.

In general, courts refuse to entertain the necessity defense when a political or moral controversy underlies the assessment of harms or when the authors of the relevant criminal prohibitions can be said to have anticipated and rejected the claim at issue. Clearly a government that has committed itself to a military campaign has made the political decision that failing to act would be worse than acting. Protestors cannot find legal cover in arguing that war is the greater evil. But courts struggle with the application of necessity to euthanasia and drug cases. Were homicide statutes and drug statutes drafted in anticipation of such cases? If not, the necessity defense remains available, if not always persuasive in particular cases.

Contours of the necessity defense

The Model Penal Code, which has generally been a template for many criminal statutes in the last thirty years, describes the necessity defense as follows:

(1) Conduct which the actor believes to be necessary to avoid an evil to himself or another is justifiable, provided that: (a ) the evil sought to be avoided by such conduct is greater than that sought to be prevented by the law defining the offense charged; and (b ) neither the Code nor other law defining the offense provides exceptions or defenses dealing with the specific situation involved; and (c ) a legislative purpose to exclude the justification claimed does not otherwise plainly appear. (2) When the actor was reckless or negligent in bringing about the situation requiring a choice of evils or in appraising the necessity for his conduct, the justification afforded by this section is unavailable in a prosecution for any offense for which recklessness or negligence, as the case may be, suffices to establish culpability. (§3.02)

Statutes based on the Model Penal Code often deviate from it by emphasizing the moral underpinnings of the necessity defense. The New York Penal Law is a good example. Conduct is justifiable when

such conduct is necessary as an emergency measure to avoid an imminent public or private injury which is about to occur by reason of a situation occasioned or developed through no fault of the actor, and which is of such gravity that, according to ordinary standards of intelligence and morality, the desirability and urgency of avoiding such injury clearly outweighs the desirability of avoiding the injury sought to be prevented by the statute defining the offense in issue. (§ 35.05 (2))

The New York statute makes clear that both the actor's weighing of relevant evils and her determination about the exigency of acting must meet "ordinary standards" of judgment. It also implies that the judgment should not be a close call.

Modern versions of the necessity defense tend to follow the Model Penal Code in reaching beyond its historical limitations.

  1. Current statutes make clear that the defense is available whether the choice of evils is brought about by natural eventsfires, earthquakes, brake failure, shipwreckor by human agency. For example, several widely discussed cases recognize a necessity defense in prison escape situations (People v. Lovercamp, 43 Cal. App 3d. 823 (1974); U.S. v. Lopez, 622 F. Supp. 1083 (1987)). Escaped prisoners, under threat of imminent physical assault and injury by fellow prisoners or renegade guards, have argued successfully that escape was the lesser evil. Older statutes, by contrast, limit the necessity defense to natural occurrences.
  2. According to most modern statutes necessity is available to defend oneself even against such serious charges as homicide. A defendant may argue that taking one life prevented the otherwise inevitable loss of several lives. For example, homicide and cannibalism have arguably been justified within groups that, stranded in the wild or at sea, faced the risk of imminent starvation. Again, older statutes often limit the necessity defense to circumstances in which the actor brings about nonlethal harm.
  3. The necessity defense is not limited to cases in which the actor is personally implicated and avoids harm to himself or his family. Nor is it limited to cases in which the actor acts altruistically. In other words, it does not matter what, if any, stake the actor had in the harm avoided as long as that harm was arguably the greater evil.
  4. Unlike duress, the necessity defense is relevant even if the threat is to property rather than to life or physical well-being.

Note that the necessity defense, as the Model Penal Code makes clear, has both subjective and objective elements. A defendant may use the necessity defense even when her assessment of the situation turns out to be wrong. It may be wrong ab initio, as in the mistaken belief that actors rehearsing a murder scene are in fact setting about to commit homicide. It may also be wrong as a prediction. The cannibals, having dined on one of their party, may be rescued sooner than they expect, making their "criminal" conduct unnecessary from the standpoint of hindsight. In such cases the law only requires reasonable understanding and predictive powers. The test is subjective.

On the other hand, the weighing of evils under necessity must fit the shared values of reasonable persons. The captain of a sinking ship cannot justify saving a cargo of valuable paintings at the cost of letting passengers drown. One cannot justify saving the life of a captain of industry or a rock star at the cost of numerous other lives on the grounds that the saved life was more valuable. This aspect of the defense alludes to shared values, and it seems to presume that they are objective.

The fact that the necessity defense presupposes a consensus of values has troubled some commentators (Brudner). They find a crude and untenable form of utilitarianism at its core, and they object that the consequences of our acts do not have natural moral parameters that permit an objective measure of the component of evil. These writers suggest that the underlying determinations about the scope and relevance of the necessity defense in particular cases are moral and complex, involving judgments about harm, intention, motive, and character. Thus, they criticize such formulations as the Model Penal Code for camouflaging this complexity.

Relation to other defenses

Self-defense and legal authority. Commentators have taken contrasting positions on the relation of necessity to other defenses. The Model Penal Code says that it expresses the overarching principle behind legal justification. Other commentators such as P. R. Glazebrook have argued that it is an interstitial concept, designed to fill gaps between other established defenses.

The Code position is easy to understand. If we consider harmful acts that are legally justified because of authorityfor example, a policeman assaulting or wounding an escaping felony suspectthe rule that justifies the policeman's act seems to reflect a general conviction that less harm overall is brought about by the coercive acts of the police than would be caused by unrestrained offenders in such contexts. The battery by the policeman is therefore the lesser evil.

Similarly, self-defense can be redescribed as justification based on lesser evils. Less harm overall may be said to occur when persons who are threatened with harm are allowed to respond with force sufficient to repel the threat than when they are not legally empowered to do so. Arguably, even when the choice is between two lives, between the homicidal aggressor and the defending victim, the use of deadly force by the victim manifests less evil than the completion of the original aggression.

The drafters of the Model Penal Code therefore conclude that the necessity defense embodies the general principle of justification. Accordingly, a lesser evils defense should be available as justification whether or not harmful conduct happens to fall under a more specialized defense such as authority or self-defense. The difficulty with this argument, as critics such as Brudner point out, is that it is one thing to say that such circumscribed defenses as authority and self-defense are justified at a more general level by reference to the goal of minimizing harm, and it quite another matter to argue that the disposition of particular cases should turn on judgments about relative harm made by individuals faced with hazard. The first is a rule-utilitarian application of the lesser evils analysis to explain familiar defenses; the latter turns it into an act-utilitarian mode of justification.

It is also clear that authority and self-defense are not simply subcategories or instantiations of the general justification of lesser evils. Some situations, for example, fit the criteria of self-defense even if they are hard to justify in terms of lesser evils. In such cases, the harm to the aggressor(s) may be as great or greater than the harm threatened. A case in which self-defense is used lethally against multiple aggressors can be made to fit the necessity formula only if (a) the fact that those killed were aggressors is assumed ipso facto to make their actions the greater evil, or (b) recognition of self-defense as justification is said to have second-order benefits that enter in the calculus, such as the effect of discouraging other aggressors, fostering respect for law, and enhancing general security and personal autonomy. Obviously the same issues arise when persons acting under cover of legal authority appear to carry out greater harm than that threatened.

Duress. Persons who act out of necessity and persons who act under duress do so in the face of threatened harm. Both the theory of necessity and the theory of duress draw attention to the pressure of exigent and extraordinary situations, pressure that prompts a harm-causing response. But necessity focuses on the anticipated consequences of the harming action, the concrete alternatives or choice facing the actor. Duress, on the other hand, focuses on the way in which the choice was made and the extent to which it can or cannot be said to reflect the free will of the actor.

Thus, acting out of necessity, an actor makes the optimal choice, aware that doing so entails a technical violation of the law. An actor under duress also chooses, but in a way that demands qualification. The pressure of the situation is said to be such that a person of reasonable firmness would not be able to resist doing harm. Such harmful actions, done as capitulation to threats, are not to be taken as an expression of the actor's will.

Necessity is generally held to be a justification, while duress is considered an excuse. A person acting under necessity chooses to act in a way that the law seems to approve and encourage, presumably for utilitarian reasons. The person who acts under duress, on the other hand, acts in a way that is generally regrettable and deserves to be discouraged, but the special circumstances make conviction inappropriate and unfair. Unlike necessity, excuses such as duress, intoxication, and provocation (which may mitigate rather than exculpate) refer to situations in which harmful choices may not be representative of the actor's character or desires.

The distinction between the justification of necessity and the excuse of duress has implications for accomplice liability. One who aids a principal acting under duress may be criminally liable (unless the accomplice was also under duress). Excuses are personal. By contrast, those who aid necessary conduct act with impunity. No legal blame can attach to those who help bring about justified acts.

Of course, some situations fall under both defenses. An actor may choose the lesser evil while also acting under duress. Consider, for example, a defendant forced to carry out a nonviolent act of theft by persons who have kidnapped members of her family and threatened to kill them. In general, duress rather than necessity would be the preferred defense in such cases.

Several commentators have criticized the distinction between necessity and duress as artificial and unconvincing. George Fletcher notes that the distinction is rarely made in foreign legal systems. He and others (Brudner, for example) point out that the utilitarian determination at the core of the necessity defense is disturbingly unclear. In cases of stealing bread to avoid starvation, for example, is the weighing to be done narrowly, balancing the threat of death for the starving offender against the financial interests of the baker? Or is the effect on general compliance for law and respect for law of such precedents also part of the account? Critics such as Colvin and Parry conclude if we cannot know what counts in the weighing, we cannot perform the calculus. They argue that what is really at issue is our moral perspective on the actor and a sense of his psychological characteristics as manifested in the actand that this empathetic adaptation of the law lies at the heart of necessity and duress alike, erasing the difference between them.

Necessity: problematic aspects

The utilitarian bases of the necessity defense are problematic if it is seen as a guide for action, a rule permitting actors to choose the lesser evil even when doing so involves a violation of law. Given the uncertain nature of the determination itself, one may question whether actors will generally be able to choose the lesser evil correctly and whether knowledge of the availability of the defense will lead to its abuse. These difficulties are mooted if one sees the necessity defense, like other defenses, not as a rule of conduct directed at actors but as a rule for courts in assessing culpability retrospectively. From this standpoint, the defense of necessity seems to rest on the principle that it is unfair to punish those who violate the law with the motive of minimizing harm and in the reasonable and sincere belief that they are doing so. Whether or not the defense may be abused, elimination of it would make the law unfair and breed disrespect of it. The cost to society of such disillusionment with law is arguably greater than the risk of abuse of the necessity defense.

To see necessity and other defenses as second-order rules governing the administration of laws rather than as first-order rules directed at actors has an important implication. The first-order prohibitions of criminal law address on intent (or mens rea generally); motive is said to be irrelevant. The defenses, by contrast, bridge intent and motive. When a defendant uses the necessity defense, she concedes that she caused harm intentionally but argues that her motive was to avoid greater harm by doing so. The moral imperative of fairness that seems to underlie necessity forces us to take motive into account.

The extent to which determinations of greater and lesser evil involve more than simple calculi and are embedded in moral assumptions is clear in many examples. Cases in which taking life is arguably the lesser evil almost always go beyond counting lives. In considering cases about persons jettisoned from overburdened lifeboats or persons cannibalized to save the ravaged survivors of shipwreck, courts have asked whether the selection of the victim was fair, whether the survivor owed a duty of care to the victim, and whether the victim acceded to his fate (see The Queen v. Dudley & Stevens, 14 Q.B.D. 273 (1884) for a historical treatment of this issue). There is no unanimity about justified killing under necessity even when these complications are absent.

Suppose a healthy autonomous individual were the uniquely compatible donor whose vital body parts, if transplanted efficiently, would save eight patients who otherwise face imminent death. It is clear that kidnapping and sacrificing the donor cannot be defended on grounds of necessity. One moral intuition is that nothing can justify compromising so decisively the autonomy and life of the donor when, unlike the joint shipwreck victims, he has not already been compromised by natural circumstances. It is clear, from this and other examples, that the notion of greater and lesser evils is both indispensable to an understanding of fairness in applying criminal prohibitions and endlessly problematic.

Thomas Morawetz

See also Excuse: Theory; Excuse: Duress; Justification: Theory; Justification: Self-Defense.


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