Kerry Kennedy: I didn't know I took sleeping pill

Kerry Kennedy, center, arrives, Monday, Feb. 24, 2014 at a courthouse for her trial in White Plains, NY.
Ricky Flores, AP

WHITE PLAINS, N.Y. - Kerry Kennedy says she did not knowingly take a sleeping pill and get behind the wheel of a car.

Kennedy testified Wednesday in her drugged-driving trial in New York that she thought she had taken her thyroid medication but must have taken a sleeping pill by mistake.

Kennedy was charged after her Lexus swerved into a tractor-trailer on a highway in 2012. Blood tests detected the sleeping drug.

Kennedy says she has taken the thyroid medication every day since 1991. She says she takes the sleeping pills when she travels.

Defense lawyer Gerald Lefcourt showed the jury a photograph of the two similar-looking pill bottles.

He showed another photo of the two different pills. Both were white and oblong, but one was slightly longer than the other.