Thomas was a passenger in the Mitsubishi Eclipse that Tyler Stasko was driving in April 2009 when it collided with the car of 45-year-old Cynthia Furr. Furr was pulling out of her neighborhood near Lake Wylie at the time.
Furr, her 2-year-old daughter McAllister and 13-year-old Hunter Holt, who was a passenger in Stasko's car, were killed in the wreck.
Stasko is now facing three counts of second-degree murder.
Thomas, who testified Wednesday for the prosecution, said Stasko was racing with another car when they came over a hill on Highway 49 and saw Furr's Mercedes pulling out very slowly in front of them.
Thomas said Stasko put on the brakes and swerved to try and avoid the collision, but could not. Moments after that, he noticed his best friend in the back seat, 13-year-old Holt, was badly hurt.
"I remember hearing Tyler moaning because he was in pain, and as I turned around I could see Hunter in the back seat turning purple," Thomas said.
Holt died later at the hospital.
Other witnesses described the collision and the aftermath for jurors.
"The Mercedes pulled out and the black car hit it, like, immediately," Lori Savio said. "The car went up in the air and started flipping through the air so there were pieces and parts flying all over."
Several witnesses described how they tried to help the victims when they got to the scene. Karl Smith was the first to get to Cynthia Furr.
"As soon as I saw her lying there, I went and checked for her pulse," Smith said.
Thomas Maloney fought back tears as he described how he, too, tried to help Furr.
"I brushed her cheek because there was dirt on it," he said.
He said he asked Smith if Furr had a pulse, but the answer was clear.
"He said there was nothing we could do," he said.
Jurors may get a chance to see the accident scene for themselves. Prosecutors want to take them there in a bus, but Stasko's attorney says the intersection has changed, including an added stoplight, so he is objecting to the excursion. Judge James Morgan has yet to rule on the prosecutors' request.
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