Oscar Pistorius didn't consciously pull the trigger the night he shot and killed his girlfriend, the Olympic sprinter testified during his murder trial Tuesday.
Pistorius said he was "overcome with a sense of terror and vulnerability" before he shot through a closed bathroom door, fearing an intruder was inside.
Defense attorney Barry Roux asked his client what he meant when he referred to the shooting as an "accident."
"I mean the situation, and the situation as a whole, it wasn't meant to be," Pistorius said.
The double amputee said he was terrified when he heard the sound of the toilet door opening.
"I didn't think about pulling the trigger. As soon as I heard the noise, before I could think, I pulled the trigger," he said.
The testimony came after the prosecution ended its cross-examination Tuesday.
Pistorius cried and his voice trembled as prosecutor Gerrie Nel challenged his account of what happened the night he shot and killed his girlfriend, Reeva Steenkamp.
Nel asked who should be blamed for shooting his girlfriend on Valentine's Day 2013.
"I'm not sure, my lady," Pistorius said, directing his answer to the judge. He repeatedly said he feared for his life and thought there was an intruder in his bathroom.
A day earlier, Pistorius testified, "I blame myself for taking Reeva's life."
He became emotional as he described finding his girlfriend slumped over by a toilet after shooting her through a closed bathroom door.
"I was saying, 'Baby hold on. Jesus, please help me,' " he said Tuesday.
Oscar Pistorius wailed on the stand today as he described his panic upon realizing his gunshots had killed girlfriend Reeva Steenkamp.
"She wasn't breathing," the track star heaved as he described the February night more than a year ago. The judge adjourned the murder trial as Pistorius' emotions unraveled and later ended proceedings for the day.
The Olympic sprinter had been explaining how he came to shoot Steenkamp, and how it didn't dawn on him at first that she, and not an intruder, may have been behind the bathroom door at which he fired his pistol.
"I didn't want to believe that it could be Reeva inside the toilet," he testified.
An emotional Oscar Pistorius apologized Monday to the family of Reeva Steenkamp, the girlfriend he killed on Valentine's Day last year, saying he woke up thinking of them and praying for them every day.
"I would like to take this opportunity to apologize - to Mr. and Mrs. Steenkamp, to Reeva's family - to those who are here today who knew her," Pistorius said as he took the stand at his murder trial.
"I can't imagine the pain and the sorrow and the emptiness that I have caused you and your family. ... I can promise you that when she went to bed that night, she felt loved," he said, his voice breaking as if he was fighting back tears.
It was the first time he has spoken in public about Steenkamp's death, which he says was an accident. He pleaded not guilty to murder when the high-profile trial opened last month.
Steenkamp's mother, June, sat stony-faced in court as South Africa's onetime Olympic golden boy choked out his statement.
Judge Thokozile Masipa also betrayed no emotion as Pistorius spoke but did once ask him to talk louder, saying she could hardly hear him.
Monday was the first day of the defense phase of the trial, following three weeks of prosecution in March.
Pistorius, who says he mistook Steenkamp for an intruder in his house in the dark, testified that he has been suffering nightmares since the killing and wakes up smelling blood.
He told the Pretoria court that he is afraid to sleep, and "if I hear noise, I wake up just in a complete state of terror." He said he is on medication, including an antidepressant and sleeping aids.
Earlier, the first defense witness, pathologist Jan Botha, talked about the wounds Steenkamp suffered when Pistorius shot her and about when she last ate.
The South African amputee sprinter put his head in his hands as Botha said that the shot that hit Steenkamp's arm was "akin to a traumatic amputation" and that she died "fairly quickly after sustaining the head wound."
Pistorius, 27, is accused of intentionally murdering Steenkamp, 29.
The defense team will call 14 to 17 witnesses, Barry Roux, Pistorius' lead lawyer, said as he opened his case.
Botha went first because of "family health reasons," Roux said, breaking with the South African legal custom of the defendant testifying first. He said Botha was the only defense witness who will go "out of order."
The prosecution rested its case on March 25 after 15 days and 21 witnesses.
Talking about his childhood, Pistorius said his mother kept a firearm in a padded bag under her pillow. His father was often not around, and Pistorius said his mother would sometimes wake her children up, thinking they were being burgled.
He said she was very supportive of him and "never made me feel any different from the rest of the kids."
"Everything I learned in life, I learned from her," he said.
He spoke about her death when he was 15 and attending boarding school. He did not know she was sick until he got a call asking him to come visit her at a hospital, he said.
Later, he got a call from doctors telling him to come immediately and arrived when she was on her deathbed. She died 10 minutes after he arrived, Pistorius testified.
She had encouraged him to be a normal child and participate in sports despite his disability, he said.
Roux took him through his athletic triumphs, including his success as a Paralympic sprinter, but also highlighted times he felt vulnerable or afraid.
He was badly injured in a boating accident in 2009, he said, which left him "a lot more vigilant about losing my life ... more fearful."
And he said he cannot stand still without his prosthetics on.
"I don't have balance on my stumps," he said. "I can't stand still on my stumps."
That could be a key to his defense. He says he fired his gun because he would have been unable to defend himself or run away when he heard what he thought was a burglar.
Shortly after a lunch break, Masipa granted an early adjournment for the day after Pistorius testified that he did not sleep the previous night. Roux made the request after establishing, through Pistorius' testimony, that the track star was tired.
The trial is due to resume Tuesday morning.
Trial to last until mid-May
Pistorius admits that he killed Steenkamp, firing four shots through a closed door in his house in the early hours of February 14, 2013. Three hit her, with the last one probably killing her almost instantly, according to the pathologist who performed the autopsy.
But Pistorius says he thought she was a nighttime intruder in his pitch-black house and believed he was firing in self-defense.
The trial, which began on March 3, is scheduled to continue until the middle of May.
Pistorius first achieved global fame as an outstanding double-amputee sprinter who ran with special prostheses that earned him the nickname "Blade Runner."
Masipa will decide the verdict in collaboration with two experts called assessors. South Africa does not have jury trials.
In South Africa, premeditated murder carries a mandatory life sentence with a minimum of 25 years in prison. Pistorius also could get five years for each of two unrelated gun indictments and 15 years for a firearms charge he also faces.
If he isn't convicted of premeditated murder, the sprinter could face a lesser charge of culpable homicide, a crime based on negligence.
The sentence for culpable homicide is at the judge's discretion.
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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