After a five-day trial, a New York jury found Kerry Kennedy not guilty of drugged driving on Friday.
In 2012, Kennedy -- daughter of the late Sen. Robert F. Kennedy and ex-wife of New York Gov. Andrew Cuomo -- was arrested and charged with driving while impaired after she crashed into a tractor-trailer while under the influence of a sleeping pill.
Why was she found not guilty?
Sleep Driving and DWIs
On July 13, 2012, Kennedy drove her Lexus SUV. erratically after taking Zolpidem, a generic form of the sleep medication Ambien. She "sideswiped a tractor-trailer on a highway before she was found, slumped over her steering wheel, her car stalled on a local road," The New York Times reports.
One of the common side effects of sleeping pills is sleep-walking and performing other actions while unconscious. Unfortunately for Kennedy and the other 60 million Americans who take prescription sleep aids, "sleep driving" isn't a defense to driving under the influence when a defendant voluntarily takes a sleeping pill.
But Kennedy was able to successfully stave off her misdemeanor charge of driving while intoxicated because of an affirmative defense called a mistake of fact.
Mistake of Fact
Kennedy testified that she took the pill accidentally, mistaking it for medication she took for a thyroid condition. This type of defense is called a mistake of fact.
The case ultimately turned on whether Kennedy should have been aware that she was feeling the drug's soporific effects -- as she was swerving and driving erratically -- and stopped the car.
Prosecutors needed to prove beyond a reasonable doubt that Kennedy did realize she accidentally took Zolpidem and knew she was under the influence of the sleeping pill, but continued to drive. Kennedy claimed that she did not realize her mistake until well after the accident.
Ultimately, jurors determined there was enough doubt in the case to reject the prosecution's case and find Kennedy not guilty, which is good news for Kennedy: She could have faced up to a year in jail if convicted, the Times reports.