Many states and the federal courts recognize defenses to criminal charges in limited circumstances when the defendant was under duress or committed the criminal offense out of necessity to avoid death or serious bodily injury. The definitions for these affirmative defenses vary from state to state and in the federal courts, with some jurisdictions treating them as the same defense, and others making the distinction that duress applies when a defendant committed the crime because someone forced them to do it, and necessity applies when the defendant was confronted with bad alternatives in an emergency situation and chose the best alternative.

The elements of the defense of duress or necessity are that (1) the defendant was facing an unlawful and imminent threat sufficient to create a reasonable apprehension of death or serious bodily injury; (2) the defendant had not recklessly or negligently placed himself in a situation where he would likely be forced to commit a criminal act; (3) the defendant had no reasonable, legal alternative to violating the law; and (4) the defendant could have reasonably believed that the commission of the criminal act would avoid the threatened harm.

Duress and necessity defenses to criminal charges may be located in a state’s court opinions or cases (common law) or in its statutes—usually in the penal or criminal code. Many states have pattern or form jury charges (questions and instructions) and include a question that may be given to the jury to determine whether the defendant’s conduct is excused by the defense of duress or necessity.

In Oklahoma, the defenses of duress and necessity are recognized as potential affirmative defenses to criminal charges under certain circumstances. These defenses can be invoked when a defendant claims to have committed an offense to avoid death or serious bodily injury. The elements required for these defenses typically include an unlawful and imminent threat that would cause a reasonable person to fear death or serious bodily injury, the defendant's lack of contribution to the situation through reckless or negligent behavior, no reasonable legal alternative to committing the crime, and a belief that the criminal act was necessary to prevent the threatened harm. Oklahoma law distinguishes between duress and necessity, with duress involving compulsion by another person and necessity involving a choice between limited, bad options in an emergency situation. The applicability of these defenses in Oklahoma is determined by case law as well as statutory provisions found in the state's penal code. Additionally, Oklahoma may provide pattern jury instructions that include questions to help a jury decide if a defendant's actions are excusable under these defenses.