Updated

A video analysis expert testified Monday that footage from an Ohio police officer's body camera contradicts his story of what happened before he fired a fatal shot during a traffic stop.

Grant Fredericks was called by prosecutors in the murder retrial of former University of Cincinnati officer Ray Tensing in the 2015 shooting of Sam DuBose, an unarmed black motorist.

The case against Tensing, who is white, is among several across the United States that have increased attention to how police respond to blacks. Tensing has said he feared for his life as DuBose drove away.

Fredericks broke down the footage frame-by-frame, explaining changes through split-second intervals in the video. Under questioning by the prosecutor, Fredericks then compared what he saw on the body cam video to Tensing's account to police investigators in a videotape jurors saw Friday.

Fredericks responded repeatedly to Prosecutor Stacey DeGraffenreid's questions with statements such as "all the images are contrary to that." He said there was nothing in the video to show that Tensing's arm was stuck in the steering wheel, that he was being dragged by DuBose's car, or that he was falling when, he said, he shot DuBose to "stop the threat" to his life.

"We can clearly see that he's not hanging onto anything," Fredericks said. Tensing had said he was "holding on for dear life."

The Spokane, Washington-based expert is to continue his testimony Tuesday, answering questions from Tensing's attorney. The defense also plans to call a video expert witness when its case gets underway.

Earlier Monday, a University of Cincinnati police officer testified he heard the gunshot came after the sound of tires squealing. Officer David Lindenschmidt agreed with another UC officer who also arrived at the scene at that point. Lindenschmidt said there was "no question" in his mind.

A civilian witness testified Friday she heard a gunshot before the car moved.

A Hamilton County jury deadlocked in November in Tensing's first trial on charges of murder and voluntary manslaughter.

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