What must be true for a defense of necessity to be valid?

For a defense of necessity to be valid, it is essential that the situation involves a clear and imminent danger. This means that the threat must be immediate and unavoidable, compelling the individual to act in a way that would usually be considered illegal, in order to prevent a greater harm from occurring. The concept of necessity is predicated on the idea that the individual's actions, though unlawful, are justified under the circumstances due to the need to avert a serious threat to life or property.

In legal contexts, a successful necessity defense demonstrates that the person faced a situation where the harm they sought to prevent was real and pressing, necessitating their illegal action as the only viable option to mitigate or eliminate that threat. This requirement serves to ensure that the justice system accurately differentiates between lawful self-preservation and unlawful behavior that could be interpreted as willful disregard for the law.

Other potential requirements, such as having no legal alternative, are important but not as crucial as demonstrating the existence of a clear and imminent danger, which is the foundational element for the necessity defense to hold.