WHITE PLAINS, N.Y. (CBSNewYork/AP) -- The prosecution in Kerry Kennedy's drugged-driving trial wrapped up its case Tuesday by calling a toxicologist to the stand. But the witness may have turned out to be more helpful to the defense.
Elizabeth Spratt, who works for the Westchester County Department of Laboratories and Research, conceded during cross-examination that the effects of the sleeping drug Ambien, which can take 15 to 45 minutes to set in, may not have been apparent to Kennedy before she climbed behind the wheel of her Lexus in July 2012.
"You can't say if Kerry Kennedy's impairment was in fact recognizable to her, can you?" asked defense attorney Bill Aronwald.
Kerry Kennedy Expected To Take The Stand As Drugged-Driving Trial Continues
"I don't know if she was aware of them," Spratt answered.
"It (Ambien) can cause amnesia where you're not aware of what you've done," Spratt continued.
The ex-wife of Gov. Andrew Cuomo and daughter of late Sen. Robert F. Kennedy was arrested after her car sideswiped a tractor-trailer on Interstate 684 in North Castle. She drove to the next exit, where she failed three of four field sobriety tests, police said.
Kennedy, 54, claims she accidentally took a sleeping pill instead of her daily thyroid medication. Kennedy's blood tests revealed a small amount of the sleeping drug zolpidem, which is marketed as Ambien. She says she has no memory of driving erratically or colliding with the truck.
Kennedy declined to comment outside court Tuesday. Her lawyer said she will take the stand Wednesday in her own defense.
Outside court, it was suggested to defense attorney Gerald Lefcourt that prosecution testimony was going his way.
"I think so, too," he said. "I hope the jury will agree."
As CBS 2's Lou Young reported, nothing so far in the prosecution's case contradicts Kennedy's version of what happened that day.
Earlier Tuesday, a New York state trooper testified that he was concerned Kennedy may have suffered a seizure or stroke after her car swerved into the truck.
Trooper Bradley Molloy said Kennedy passed several drug tests that he administered at the police station. The tests included having Kennedy follow the tip of a pen with her eyes, stand on one leg and touch the tip of her finger to her nose, Molloy said.
He said she was very polite and cooperative as she struggled to understand what had happened, WCBS 880's Irene Cornell reported.
Kennedy told the trooper that she had consumed some carrots and a cappuccino that morning and had slept about eight hours the night before.
Molloy said Kennedy also told him she was concerned that she might have accidentally taken a sleeping pill instead of her thyroid medication, which were next to each other on her medicine cabinet.
"The defendant was not impaired by any drug,'' Molloy said. "I feel she may have suffered a medical condition while driving.''
The defense case opened with two character witnesses. The Rev. Gerard Creegan, a family friend, said he's known Kennedy since 1975 and had been to Kennedy family gatherings including "weekends at the Cape." He said Kennedy had helped him with human rights work in the Dominican Republic and was "very honest" and "very sober."
Kennedy's younger sister Rory Kennedy, a documentary filmmaker, then took the stand and said Kerry Kennedy "has a stellar reputation for honesty." She said she also has "a reputation for sobriety and general healthy living."
On Monday, a North Castle town police officer Joel Thomas said he had administered four field sobriety tests, involving eye movements, walking and turning, reciting part of the alphabet and standing on one leg. Kennedy only passed one, reciting the alphabet from J to T, he said.
Motorists also testified Monday that Kennedy swerved her car into the truck, damaging the car and blowing a tire, but kept driving. She was later slumped at her steering wheel and disoriented.
Toxicology Expert: Kerry Kennedy May Not Have Recognized Ambien's Effects
In his opening statement Monday, Lefcourt said Kennedy was not disputing that she drove erratically.
"The zolpidem kicks in. It shuts her down. She's in a state of sleep-driving,'' Lefcourt told jurors. "Kerry Kennedy was ambushed by Ambien."
Lefcourt said the prosecution's case is based on speculation that Kennedy knew she mistakenly took the sleeping pill and yet continued to drive, 1010 WINS' Al Jones reported.
Prosecutor Stefanie DeNise said even if the pill was taken accidentally, Kennedy violated the law "by failing to stop and pull over as she felt the onset of symptoms.''
"She would've known," DeNise told the jury. "By failing to stop the car, she put people in danger."
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