This is a key day, today, in the trial of Oscar Pistorius. He is once again on the stand. This is the third day of relentless cross-examination. This morning, ABC's lama Hasan is at the courthouse in... See More
This is a key day, today, in the trial of Oscar Pistorius. He is once again on the stand. This is the third day of relentless cross-examination. This morning, ABC's lama Hasan is at the courthouse in Pretoria, South Africa, with the very latest. Lama, good morning. Reporter: And good morning to you, Amy. Just moments ago, the court has resumed for the day earlier than Normal. This after a day of grilling, after the prosecution going after Oscar Pistorius, telling him there were no intruders that night. That reeva steenkamp was not scared of anything. The prosecutor telling Pistorius, she was scared of you. Did Pistorius warn his model girlfriend that were intruders inside his home before shooting her? You did not check with her. She's awake. You did not say, reeva, did you hear that? There was no doubt in my mind. I didn't need confirmation. Reporter: Pistorius said he told her to get down and call the police. But this morning, admitted he didn't check to see if she had done so. A reasonable person would have looked where reeva was, looked if she was safe and if she panicked. But you didn't. You just grabbed a gun. Reporter: Earlier, the lead prosecutor questioned why the blade runner believed an intruder broke into his home when he had such an elaborate alarm system. I deacted the alarm in my room. That's correct, my lady. Now, you don't know. That doesn't make sense. You have two different things. Reporter: Pistorius becoming flustered over questions about his alarm. And again, had to fight back tears on his third day of cross-examination. Causing the judge to ask if the olympian had run out of stamina. If you are tired and the reason you're making all of the mistakes is because you're tired, you must say so. Reporter: When Pistorius is being cross-examined in the courtroom behind me, under the south african judicial system, he is not allowed to confer with his lawyer. So, he's on the witness stand, completely on his own. Why would this question make you emotional? Because it's not the person that I cared about. I don't see how people don't understand that. Ma'am, the witness is clearly in distress. Yes. Give him a moment. Reporter: And that judge also scolding the lead prosecutor, gerrie nel, for repeatedly calling Oscar Pistorius a liar. This, as she's trying to control an already intense courtroom. Amy? Lama Hasan, thank you. And with us now, ABC's chief legal affairs anchor, Dan Abrams. And the key point that the prosecutor gets to. How did Oscar Pistorius not know reeva steenkamp was not there when he went to get the gun? This is the question. How did he not know she was there? How did he not say honey, I hear something. And anytime he would hear noises, he would immediately say, I just heard something. The two, key things we've heard today are the prosecutor really focusing on how would you have not known she was there? And number two, why did you shoot at the door? What was it that led you to shoot, even if you thought that there was an intruder? What did this supposed intruder do that led you to shoot four shots at the door? It is the crucial question in this case. And then, something else very interesting. The judge focusing on the alarm system. The fact it didn't work that night. Or it didn't go off that night. There's a broken window in his home. For someone who is so concerned about security as part of his defense, it's questionable. Right. Pistorius said I was always worried about crime. I was worried about a break-in. And that goes to my mindset saying this would happen. But the prosecutor is saying, the alarm didn't go off and you had a broken window and there weren't repairs made to the alarm system. What happened to the guy that
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