(NEW YORK) -- Kerry Kennedy was under the influence of a sleeping aid when she was involved in a crash with a tractor-trailer on a New York highway and left the scene.
A toxicology report shows that Kennedy, the ex-wife of New York Governor Andrew Cuomo, had a generic version of the powerful sleep aid Ambien in her system when she crashed and was later found slumped over the steering wheel.
Her doctors claimed she had a seizure, but Kennedy, 52, told police she may have mixed up her medications, taking a sleep aid instead of her thyroid pill.
A Kennedy family statement said that Kerry Kennedy "voluntarily took breathalyzer, blood and urine tests -- all of which showed now drugs or alcohol whatsoever in her system."
Kennedy pleaded not guilty to a misdemeanor charge of driving under the influence of drugs at her July 17 arraignment.
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