A woman was pulled over in upstate New York with her blood-alcohol level four times over the legal limit — an open and shut case, right? Actually, no: a judge threw it out after dingin that her body brews its own alcohol.

The woman was pulled over shortly before Christmas in the town of Hamburg and blew a tremendous alcohol level that must have taken police by surprise. However, a judge tossed the charges because she suffers from what is known as “auto-brewery syndrome,” according to a CNN report.

Even her lawyer, Joseph Marusak, admitted he’d never heard of such a condition in his years of defending clients. But he said despite blowing four times the legal limit, she was released immediately because she was exhibiting no symptoms of drunkenness.

So Marusak took to the Internet to figure out just what was going on, and he found out about auto-brewery syndrome.

It’s definitely not a common ailment. The CNN report quotes a medical expert who says that she knows of about 10 people who are diagnosed with it. She knows that they can function at alcohol levels of 0.30 or 0.40 — way beyond the legal limit of 0.08. At that level, regular people would be on the verge of death from alcohol poisoning, but these people don’t have any ill effects.

Scientists believe that the small bowel is to blame, and that it involves an abnormal amount of gastrointestinal yeast converting into regular food carbohydrates into ethanol.

Marusak’s client, who remains unnamed, will be treating her condition with anti-fungal medication and a new diet that is free of yeast and sugar.