Control Unlikely After Pedal Error, Expert Says

If George Russell Weller mistook the accelerator for the brake when he drove his car through the crowded Santa Monica Farmers’ Market three years ago, there was practically no chance he could have regained control of his car, an accident expert testified Thursday.

“To a greater than 99% degree of certainty, it can never be corrected,” psychologist Anthony Stein said of so-called pedal error -- drivers mistaking the gas pedal for the brake. Drivers react two ways when they are unable to stop: “They hit the pedal harder or they start pumping” the pedal, he said. When the car fails to stop “the only thing they are focused on is, ‘Why isn’t the brake working?’ not ‘What else can I do?’ ” Stein said.

Weller is charged with 10 counts of manslaughter in the July 16, 2003, incident in which 10 people were killed and more than 60 injured.

Stein, who researches human factors in vehicle accidents, testified as a paid witness for the defense in the trial at Los Angeles County Superior Court. Weller’s lawyers contend the tragedy was an accident, not a crime.

The California Highway Patrol concluded that pedal error is the best explanation for the tragedy, but noted that Weller caused the incident by failing to stop after he had collided with another car moments before.

Witnesses testified that after Weller, now 89, was involved in the fender bender, he accelerated into the market at Arizona Avenue and 4th Street. The prosecution has suggested that he was fleeing the scene of the earlier accident and is trying to show that the market incident resulted from Weller’s gross negligence.

Deputy Dist. Atty. Ann Ambrose questioned Stein’s conclusion, noting that the research he cited involved drivers repeatedly hitting a malfunctioning brake pedal. The drivers were not pumping or pushing the accelerator.

Stein answered that the drivers’ responses should be the same whether they were pushing a broken brake pedal or mistaking the gas pedal for the brake. “The human perception is, ‘The brake is not doing what I want it to do,’ then panic,” he said.

It would also be impossible to perform a test for pedal error, because “you can not make someone do the wrong thing” without being conscious of their action, he said.

A driver’s age is not relevant once pedal error occurs, Stein said. When panicked, “tunnel vision results in the brain being totally focused on what is in front of you.” A driver would be “looking straight ahead, gripping the wheel,” Stein said.

Several witnesses testified that they saw Weller with both hands on the steering wheel, in the 10 o’clock and 2 o’clock positions, and that he was looking straight ahead.

The CHP analysis of the accident ruled out mechanical, environmental and medical problems, leaving only human error. Richard Wong, head of the CHP investigation, earlier testified that Weller actively steered his Buick as he drove through the market.

Ambrose asked Stein if someone could steer in a panicked state after pedal error. Stein said steering is not possible, but a car can move from side to side with little input to the steering wheel. A driver’s “hands can move if a vehicle is bouncing around; that’s not overt steering,” he said.

The CHP concluded Weller never braked; his car stopped because it was dragging a shopping cart, a trash can and a body.

peter.hong@latimes.com