Insanity Defense in Georgia: Understanding ‘Not Guilty by Reason of Insanity’ vs. ‘Guilty but Mentally Ill’ Verdicts

Georgia law draws a hard line between having a mental illness and being legally insane. The standard is set in O.C.G.A. § 16-3-2: If, at the moment the crime happened, a person couldn’t tell right from wrong because of a mental illness or defect, they aren’t criminally responsible. There’s also O.C.G.A. § 16-3-3, which covers situations where someone acts under a powerful delusion, one so strong that, if it were true, their actions wouldn’t be illegal.

The law zeroes in on the person’s mental state at the time of the act, not their medical history in general.

Two Verdicts That Change the Outcome

When the insanity defense is on the table in Georgia, the jury has more than just “guilty” or “not guilty” to choose from. Under O.C.G.A. § 17-7-131, they can return:

• Not Guilty by Reason of Insanity (NGRI): This isn’t a walk out the door. Instead, the person is sent to a state mental health facility and stays until a court decides they’re no longer a danger.
• Guilty but Mentally Ill (GBMI): The person is convicted and serves a regular sentence. They may get mental health treatment during incarceration, but they still serve the time.

If neither applies, the case ends like any other, with a standard guilty or not guilty verdict.

What the Defense Must Show

In Georgia, the defense, not the prosecution, has the job of proving legal insanity. The burden is “by a preponderance of the evidence,” meaning it’s more likely than not that the person met the legal standard at the time. Lawyers often bring in psychiatric experts, past medical records, and witness accounts to support the claim.

The Georgia Supreme Court’s decision in State v. Wierson is a good example: Even if someone stopped taking prescribed medication, they could still use the insanity defense if they truly lacked the capacity to understand what they were doing when the crime happened.

Why You Should Talk to Us Early

An insanity plea isn’t simple. It takes time, planning, and a clear strategy. Wait too long, and you may lose the chance to raise it effectively.

At Morris & Dean, LLC, we’ve worked with clients facing these high-stakes situations. If you or someone you care about is in this position, call 706-222-3790 or reach us through our intake form today.