PRETORIA, South Africa --
The Olympic athlete, charged with murder in the death of girlfriend
But Masipa cautioned Pistorius that if he was making mistakes because he was tired, he must say so.
"It's important that you should be all here when you are in that witness box," she told him. "If you are tired and that's the reason you're making all these mistakes you must say so. It doesn't help to say it won't change."
"The question is, are you too tired to proceed, because you can be at a disadvantage when you're in that witness box. Are you making the mistakes because you're too tired?"
Pistorius responded that he was not making mistakes because he was tired.
State prosecutor Gerrie Nel several times called Pistorius a liar, saying that was the reason he kept making mistakes and contradicting himself. The judge warned Nel not to call Pistorius a liar while he was in the witness box.
Pistorius has pleaded not guilty to murder, contending that he thought Steenkamp was an intruder when he fired four shots through the door into an enclosed toilet off the bathroom of his home. He also pleaded not guilty to two counts of recklessly discharging a gun and one of unlicensed possession of .38-caliber ammunition.
Pistorius contended he formed no intent to kill an intruder because he "didn't have time to think."
"I was never ready to shoot," the double-amputee athlete told the court Friday, but he admitted that he had released the safety on his gun "so that if I needed to use my firearm, I could."
"You were ready to shoot," countered Nel.
"That's correct," my lady, conceded Pistorius, addressing the judge.
Nel asked why Pistorius didn't simply take Steenkamp, who he has said he believed was still in his bedroom, and retreat downstairs to safety.
Pistorius answered that it was his instinct to go toward danger because "that's who I am."
He admitted he didn't check how Steenkamp was.
"So you wanted to go and confront these robbers, and you did, by firing," Nel said.
"That's correct, my lady," Pistorius replied.
At one point Pistorius said when he was outside the bathroom he heard the sound of the toilet door either closing or being kicked, making him certain an intruder or intruders were in the house.
Minutes later, he stated, "I never ever said that somebody kicked the door."
When Nel pointed out the contradiction, Pistorius retracted the statement: "I made a mistake, my lady. I apologize and I don't know why I said that," he said, adding, "I'd forgotten about that point."
Nel said the mistakes were coming because he had to keep up with an untruth.
"I put it to you that your mistakes are as convincing as your evidence in the way you give it and that's a problem," Nel said. Pistorius said he didn't want to comment on that contention.
Pistorius recalled that he was in the bathroom shouting at Steenkamp to call the police.
Nel said this was the most improbable part of Pistorius' story: That he was yelling at Steenkamp, just a few yards away behind the toilet door, and she didn't respond.
"She would have been scared. I think she would have kept quiet for that reason," the athlete said. He said Steenkamp had been involved in a similar incident in the past when she locked herself away and hadn't been able to speak to anyone for a day.
Nel retorted that "she wasn't scared of anything. She was scared of you."
The prosecutor later said, "In fact you knew that Reeva was behind the door and you shot at her. That's the only thing that makes sense."
"That's not true, my lady," Pistorius said.
Pistorius said Steenkamp didn't scream when he shot her. A state ballistics expert and defense pathologist have testified that the first shot hit Steenkamp's hip. State pathologist Gert Saayman testified it would be extremely unusual if someone with a wound of that kind did not scream.
"At no point did Reeva shout or scream," Pistorius testified. "I wish she let me know that she was there."
Asked if he was sure she didn't scream, Pistorius conceded he would not have been able to hear her over the sound of the gunshots, which he said left his ears ringing.
"I was screaming, I couldn't hear myself scream," he said.
Nel focused on Pistorius' ability to describe his thoughts and other details up until the point he shot at the door, when he insisted he didn't have time to think his actions through.
"It's not that easy. You cannot tell the court, 'I didn't have time to think,'" Nel said.
The prosecutor said he had heard a lot about what Pistorius thought and felt at shooting the door, but he had never heard him talk about Steenkamp's unthinkable last moments, as she was shot.
"I've thought about it many times, what Reeva must have thought in the last moments that she lived," Pistorius said.