What Is an Affirmative Defense?

Florida State Attorney Angela Corey announced on Thursday that George Zimmerman had been arrested and would be charged with second degree murder. During that press conference, a reporter asked her about the possible implications of Florida's "Stand Your Ground" law.

In response, she explained that the law provides Zimmerman with an "affirmative defense," and that if it was raised, it would be dealt with in court. She further vowed to fight the "affirmative defense."

What's an affirmative defense?

An affirmative defense is a justification for the defendant having committed the accused crime. It differs from other defenses because the defendant admits that he did, in fact, break the law. He is simply arguing that he has a good reason for having done so, and therefore should be excused from all criminal liability.

In criminal trials, the most common affirmative defenses include self-defense, defense of others and insanity. Duress, entrapment and involuntary intoxication are used less often.

To see how one of these defenses works, let's look at the pending Trayvon Martin trial. George Zimmerman will undoubtedly argue that he acted in self-defense as defined by Florida's "Stand Your Ground" law. There's absolutely no question that he killed Martin. If he can successfully prove he acted in self-defense, the law says he cannot be convicted of murder. He will go free.

The same analysis would apply to almost all of the affirmative defenses -- if accepted by the judge or jury, the defendant goes free. The only affirmative defense that differs is insanity. When defendants are found not guilty by reason of insanity, they are often placed in psychiatric institutions.

Still, a temporary stay in a hospital has got to be better than a prison.

Related Resources:

• What are my possible defenses? (FindLaw)
• Affirmative Defense (FindLaw)
• 'Stand Your Ground' Laws: State by State (FindLaw Blotter)