HOUSTON (AP) — A collision expert testified that a woman accused of killing her husband by running him over could only have struck the victim once with the car.

Expert Steve Irwin brought a model Mercedes to show jurors the route that defense attorneys say the sedan took in a hotel parking lot July 24, when Clara Harris, 44, is accused of running over her husband after finding him with another woman.

Irwin told jurors Friday that Clara Harris struck her husband once, causing his body to fall on top of the hood of her silver luxury sedan. As the car slowed, Irwin said, the body fell to the ground and was rolled over by the car's front tires.

Irwin said his findings were based on his own 1,400 measurements in the hotel parking lot, police reports, eyewitness testimony and skid marks left by the Mercedes. He told jurors that based upon his projections, the turning radius on Clara Harris' sedan would not have allowed her to hit her husband more than once.

"If you get in this car and make a turn and rocket left you can never get back to that mark," Irwin said, describing blood left on the pavement where David Harris' body landed 65 feet from where he first was hit. "The turning radius is not going to let it happen."

Defense attorneys contend the orthodontist's death was accidental.

Irwin, the first defense witness after prosecutors rested their case Friday, testified Harris's car had a turning radius of 20 feet, preventing her from circling and hitting the body numerous times as prosecutors have alleged.

Under cross-examination by prosecutor Mia Magness, Irwin admitted the blood spot didn't accurately represent the victim's 5 foot, 9 inch frame.

"What you're really telling this jury is ... you can't tell them she never ran over that body again because you don't know where the body was," Magness said.

"Fair enough," Irwin replied.

Witnesses at Harris' trial have disagreed on the number of times her husband was hit but all have said he was struck multiple times. One prosecution witness said David Harris was struck twice; another said five times.

The trial resumes Monday.

If convicted, Clara Harris faces up to life in prison. If jurors determine she acted under the legal definition of sudden passion, they could consider a lighter sentence of two to 20 years in prison.