PRETORIA, South Africa (AP) -- Standing with his arms straight out in front of him and gripping an imaginary pistol in court, a South African police ballistics expert showed Tuesday how he estimated the trajectory of the four bullets Oscar Pistorius fired through a toilet door while standing on his stumps to kill his girlfriend.
Capt. Christiaan Mangena said Pistorius shot at a slightly downward angle into the cubicle where Reeva Steenkamp was, with the bullet holes around a meter (3 feet) high in the wood door. Pistorius was about 2.2 meters (7 feet) away from the door when he shot, Mangena said.
Mangena investigated how the double-amputee athlete shot Steenkamp on Valentine's Day last year by reassembling the broken toilet cubicle door, re-hanging it in Pistorius' bathroom and then tracing the direction of the bullets through the holes in the door and, in the case of one that missed Steenkamp, to marks on the walls inside the toilet cubicle. Mangena said he used thin rods and a laser beam to determine the path of the bullets that killed Steenkamp.
The testimony, which began to deal with the crux of the case, came late in Tuesday's court proceedings. Mangena is expected to reveal his conclusions in testimony Wednesday.
By recreating the angle of the shots and matching that with the wounds Steenkamp suffered in the head, hip and arm, Mangena may be able to describe what position the model was in when she was hit. With Steenkamp's mother June attending court, Mangena explained he had referred to post-mortem photographs to understand the bullet wounds.
"I have to see the injuries sustained. I have to see the position of injuries sustained," he said.
Mangena's evidence could help show if Pistorius intended to kill Steenkamp.
If she was standing up and backed away from the door and in a corner when she was hit, it might cast doubt on Pistorius' version that his girlfriend had gone to use the toilet, without him knowing, in the middle of the night and he mistook her for a dangerous intruder.
If Mangena can conclude which bullet hit Steenkamp in the head, it may also make it possible for the court to decide if she was able to scream during the shots, as prosecutors say she did. Pistorius says Steenkamp did not scream and he therefore did not know he was shooting at her in the pre-dawn hours in his darkened bathroom.
Pistorius, 27, is charged with premeditated murder for killing Steenkamp, 29. He pleaded not guilty and says he shot her accidentally and then struck the toilet door with a cricket bat to get to her after realizing what he had done. Prosecutors charge that Pistorius, a boundary-breaking disabled athlete who ran at the Olympics, killed Steenkamp in a rage after a loud argument that caused her to flee to the toilet.
Pistorius said he was on his stumps when he shot and prosecutors now do not dispute the assertion after initially alleging he was on his prosthetic limbs.
Earlier Tuesday, defense lawyer Barry Roux argued, through a minute examination of police photographs of the blood-spattered scene, that evidence was moved around in violation of procedure during the investigation. Warrant Officer Bennie van Staden, a police photographer, took photos of the scene, including of blood stains, bullet casings, the gun and the cricket bat found inside Pistorius' bathroom. Roux has challenged previous police witnesses, seeking to uncover contradictions and reported mishaps to support his argument that officers bungled the investigation, an allegation made by the defense at the start of the trial.
In a painstaking process, Roux studied many photos taken by van Staden and another police officer and pointed out that objects had been moved. Roux also used time of day records on the images to show that the two policemen taking photographs were in the same room at points, even though van Staden testified he was working alone.
Associated Press writer Torchia reported from Johannesburg.
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