A police forensic expert testified Wednesday that it appeared Oscar Pistorius was not wearing his prosthetic legs when he knocked down a bathroom door with a cricket bat after killing his girlfriend.
Pistorius has said he tried to break open the door when he realized he'd shot his girlfriend, Reeva Steenkamp, last year.
Forensic scientist Col. J.G. Vermeulen took the stand to discuss marks on a cricket bat and a bent steel plate found in the bathroom door after the shooting.
In his testimony, which used the actual bathroom door, Vermeulen had to squat to highlight the marks on the door. He said the location of the spots on the door is consistent with Pistorius not wearing his prosthetic legs.
"From the forensic evidence, he was on his stumps," Vermeulen said.
The door will also be used to show the trajectory of the bullet, which both sides can use to argue whether it was premeditated murder or not.
Pistorius, the first double-amputee to run in the Olympic Games, regularly wears prosthetic legs. If he was not wearing them at the time, the trajectory will be lower and the defense can argue that he was feeling vulnerable and didn't have time to think.
Pistorius has pleaded not guilty to murder in the shooting on Valentine's Day last year.
He admits killing the 29-year-old by shooting her through a locked bathroom door in his house. However, he says he mistook her for a burglar in the middle of the night, and argues it was a tragic but understandable mistake.
Friend: Pistorius sped, fired
Before the scientist took the stand, a friend of Pistorius who was with him twice when guns went off in the South African track star's hands was back on the stand to testify against him.
Prosecutors trying to convict Pistorius of murdering his girlfriend have charged him with breaking gun laws on both occasions.
The incidents were not connected to the fatal shooting of Steenkamp, but prosecutors appear to be using them to demonstrate that Pistorius is not safe around guns.
He grinned and shook his head as his friend, Darren Fresco, testified Wednesday about speeding during an incident that ended with the track star firing a shot out the sunroof of the car.
Pistorius was driving about 200 kilometers per hour, Fresco said. He said Pistorius was "furious" that police had touched his gun in one of the incidents, and later fired a shot out the sunroof of the car Fresco was driving.
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