the latest in the high-profile trial of george zimmerman, standing accused of killing trayvon morton. The lead detective in the case, a witness for both sides. Taking the stand for his second day.... See More
the latest in the high-profile trial of george zimmerman, standing accused of killing trayvon morton. The lead detective in the case, a witness for both sides. Taking the stand for his second day. Now, matt gutman is in stanford, florida, with the latest. Reporter: Good morning, josh. It was a pivotal day in court. That witness you mentioned serino, was the lead investigator. He said he thought zimmerman was being truthful. Jurors spent hours listening to the audio and videotapes of the man whose fate they are about to decide. It was george zimmerman's day to testify. And he kept punching me. Reporter: Only, he didn't have to take the stand. Instead, the prosecution rolling out five versions of his story. The statement and interrogations at the police department. Then, this re-enactment. He was hitting my head -- i thought my head was going to explode. Reporter: To the lead homicide investigator, chris serino, seen here, as he walks through the recreation of the encounter with trayvon martin. All those remarkably consistent. Either h e was telling the truth, or he was a pathological liar. Were there they indications that you thought he was a pathological liar? No. Reporter: A fatal blow to the prosecution. The investigators said, i think he was telling the truth. How do you overcome that? George zimmerman testified thanks to the state. And now, doesn't have to take the witness stand to be challenged. Re. Reporter: And zimmerman's description, jarring sometimes, as he described that fatal moment. Reporter: Its 25th witness, a star prosecution witness, appearing to shine for the defense. You had fairly specific evidence that mr. Zimmerman was acting in self-defense that night, correct? I had information that would have supported that. Yes, sir. Reporter: Serino even admitting he buckled under the pressure to make an arrest. You were also under quite a deal of pressure to get this case moved forward, correct? Yes, I was. Reporter: While it seems to lose a round, the prosecution did score a few points. Did you tell him he was neighborhood watch? Wonder what the hell was doing come out of your car, we probably wouldn't be here. Reporter: We expect serino to be back on later this morning. The person not to expect, is the person who knows exactly what happened, is george zimmerman. The analysts say he's unlikely to do better telling his story than the audio and videotapes. Josh? Matt gutman, thank you for that. We want to turn to dan abrams, also in sanford, florida. Covering this trial. I want to ask you about the star witness for the both sides. The prosecution has zimmerman's various accounts played in court. And once again, a prosecution witness seems to have helped the defense. What does it do to the prosecution's case? The purpose of introducing all of these statements was to show inconsistencies. And there are some. For example, were there bushes there that trayvon martin could have come out of? Why did he mention the bushes one time and not another time? Exactly what did trayvon martin say at the time? But when you look at the big picture, the statements are strikingly consistent about what happened that night. And you see that mark o'mara keeps bringing up one interesting point. And that is george zimmerman would not have known that the video surveillance system in the community wasn't working. Why is that important? If it had been working, it would have been able to support or disprove exactly what zimmerman was saying that night and the day after. I want to ask you about chris serino, again, the lead investigator. Back on the stand today. Could he still help the prosecution's case? Well, this is now the cross-examination of serino. It's hard to figure out exactly how he is suddenly going to change and help the prosecution's case. I mean, look. Parts of what he says are helpful. The problem is, when you look at the big picture and you look at him in conjunction with the other witnesses who have testified, he does seem to help the defense more than he does the prosecution.
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