Occasionally, a person faces a situation that requires doing something illegal in order to prevent serious harm. In such a situation, the defense of necessity, which is also called the "lesser of two evils" defense, may come into play. (For more on this area of law, see What's the difference between duress and necessity?)
Most states recognize the necessity defense in some form, but even when permitted, it's rarely successful. And, traditionally, the necessity defense isn't available to a defendant who kills an innocent person, regardless of the circumstances.
A defendant who raises the necessity defense admits to committing what would normally be a criminal act but claims the circumstances justified it.
Normally, to establish a necessity defense—a tall order—a defendant must prove that:
A defendant has the best chance at succeeding with this defense when the criminal act is minor and the potential harm is significant (life-threatening or catastrophic).
A defendant was convicted of driving with a suspended license for traveling to a telephone to call for help for his pregnant wife. He didn't have his own phone, and his wife was experiencing back and stomach pains. He first walked to his only neighbor's house to use the phone but found no one home. He then drove a mile and a half to the nearest phone to call his mother-in-law for help. On the drive back home, the police stopped him for a broken taillight and arrested him for driving with a suspended license. Recognizing that circumstances beyond one's control sometimes force a defendant to engage in illegal conduct, the appellate court ruled that the trial court should have allowed the defendant to present a necessity defense. (State v. Cole, 403 S.E.2d 117 (S.C. 1991).)