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Continuing Coverage of the George Zimmerman Trial; Voice Analyst Testifies in Zimmerman Trial

Aired July 1, 2013 - 09:30   ET


DR. HIROTAKA NAKASONE, VOICE ANALYSIS EXPERT: Of those, 16 seconds was overlapped by other voices and less than three seconds was the only area where not else but screaming was coming through.

RICHARD MANTEI, PROSECUTOR: What were you able to --


CAROL COSTELLO, CNN ANCHOR: We're going to continue to monitor this for you. When we come back, we'll fill you in on what you me missed, but we gotta take a break. We'll be right back.


COSTELLO: All right, Dr. Nakasone is continuing his testimony. He's talking about the voices heard on that 911 call, specifically if you can tell if the voice is an old voice or a young voice. Let's listen.


NAKASONE: We know people make mistakes. When we hear on the phone someone's voice say a young's voice coming through and I may think, oh this guy's very young, 20 years old probably but it can turn out to be 55-year-old talking or sometime a (INAUDIBLE) judge. I think everybody may have gone through this before too. You may think this man is very old, maybe 30, 35 but he can turn out to be only 18 or 19. This also depends upon the individual too. Guessing age is a little complicated.

MANTEI: Tell me what you know about, for example, just the generalized parameters of the pitch of a voice as it relates to ages, genders, and stages of development.

NAKASONE: Pitch is -- well let me just define quickly -- pitch is the psychological perception of actual vibrations of vocal cords. So, like when I'm talking in this courtroom right now, probably my vocal cord is opening and closing approximately 100 times per second. So, 100 repetitions of the same thing per second is called 100 hertz. Maybe 120. The average pitch of the grown or adult male is somewhere around 120 hertz. On the other hand the average adult female voice has about 220 hertz per second. It's twice as high as men. On the other hand a small child produce somewhere around 400 hertz on the average. Small children has highest known pitch.

This is based upon the speech samples while everybody is talking in a normal speech, carrying out conversation. This pitch goes all over the place when someone in extreme conditions like roller coaster ride or pilot's voice right before the crash to the ground or somebody that goes through extreme emotional status. The pitch is known to raise way higher into 500, 600, 700 hertz regardless of the age.

Normally we're accustomed to hearing a person's pitch but they say another phenomena (INAUDIBLE) when we speak pitch is the baseline, pitch is sort of a source of energy, but the reason what we hear distinctive sounds from me is not because of the pitch. It's created by resonance patterns created by a tube, formed inside a human vocal tracts. Tube starts from the lips all the way down to the top of the vocal cord. It's somewhere around 15 to 17 centimeters. This tube is constantly changing and creates a resonance. That resonance can be also changed when the person uttering something under extreme emotional state.

MANTEI: Doctor, have you yourself made attempts and actually taking exemplars and been able to estimate the age or at least the general age of a speaker with prior samples?

NAKASONE: It occurred to me but I decided it was not possible to determine.

MANTEI: On this one?

NAKASONE: On this particular case.

MANTEI: But you've done that before?

NAKASONE: Yes, I have analyzed variety of voices in the past.

MANTEI: Sometimes you're able and did I understand, sometimes you're not?

NAKASONE: That is true. I have analyzed voice coming from 16-year-old young men against 20-year-old men I don't quote the case, but we were able to identify the voice and in other cases more often than not we not recommend to police department or field office, do not try to get voice samples from younger boy who are going through potential voice change. This puts a very special uniqueness in situation because depending upon individuals, one person goes through and complete his voice change in rather short period of time. He may start at 12. He may complete his voice change within a year. Some individuals may go through extended period of time before his voice finally gets established.

MANTEI: That could take as late as how in life?

NAKASONE: I can't really quote an exact a year but usually --


COSTELLO: We're still trying to figure out the relevancy of this testimony. As we continue to do that, we're going to take break. We'll be back with much more in the NEWSROOM.


COSTELLO: All right. We're continuing to listen to testimony from Dr. Nakasone, he's an FBI voice analyst, and he's talking about the voices on the 911 call that we heard so much about. Basically he's saying there's no way to tell whose voice that was screaming on the 911 tape, which is of course what we kinda already knew. Two attorneys on my panel today, Page Pate, Sunny Hostin, are confused about this. Jason Johnson who is a court observer, much like I am. If you're sitting on the jury, Jason, and you're looking at this witness, you're saying what's the point?

JASON JOHNSON, CHIEF POLITICAL CORRESPONDENT, POLITIC365: They might be nodding off like George Zimmerman on day one. It seems like really long build up to whatever it is the prosecution is trying to argue. I don't really understand what their point is. At the end of the day, I think people will listen to the tape, the jurors are going to decide on their own who they think they hear. I don't think any expert or witness could sway them.

COSTELLO: What are they trying to do, do you think Page? I mean, he's now talking about how you can't tell whether it's a young person's voice on the tape, or an adult, and then the prosecuting attorney kind of turned it to like voices you hear in real life not on tape and can you tell if those person is young or old if you hear those voices too from far away.

PAGE PATE, CRIMINAL DEFENSE ATTORNEY: It's really hard to understand. I mean, as a prosecutor, we all know you have to call fact witnesses even if they don't support your theory of the case. You gotta get it out there, because if you don't do it, the defense lawyer will. That's not true with experts. It seems like this expert is undercutting one of the earlier prosecution witnesses we heard from last week who seem to suggest it was the younger person who gave the scream. I really have no reason to give you as to why he's doing this especially at this point in the case.

COSTELLO: Sunny, you've been listening to this testimony for what about 20 or 30 minute now. Can you make sense of it yet?

SUNNY HOSTIN, CNN LEGAL ANALYST: Yeah, and I think we also need to take a step back. We all know about the frye hearing. We all know this information. The jury doesn't. The jury is listening to this with fresh ears and watching this witness with fresh eyes, if they were telling the truth. That's the first point.

The second point is we know that this witness is talking about voices, talking about older voices versus younger voices and we also have been told that perhaps someone from Trayvon Martin's family may get on the witness stand and identify the voice as that of Trayvon, the voice that was yelling for help.

This kind of testimony coming from an expert could support that kind of testimony. I don't think it's so out there that this person is getting on the witness stand, an expert, having been with the FBI for so many years giving that context. Yes, sometimes you can identify the difference between a younger sounding voice and older voice. He has done it before. It's making a little more sense to me. It's becoming much clearer. I suspect that's where it's going.

COSTELLO: Although as Jason Johnson pointed out, he also testified that when a grown man is afraid, he sounds like a younger person.

HOSTIN: Well that's right, that's right. And he says that pitch -- he is saying that pitch sometimes gets much higher when you're under stress but again, if Trayvon Martin was already young, his voice hadn't been was young, his voice hasn't been established yet, if he's under stress then you're even listening to a higher pitch and you've got other witnesses that are saying, Rachel said he had a baby voice.

You've got some of the witnesses saying well I thought it was a younger sounding voice and then if the state puts on someone from the family that says I know that's my son or I know that's my nephew, that could carry a lot of weight. And so you know I think I know where this -- this witness is going.

COSTELLO: Until the defense puts George Zimmerman's family on the stand and they say I know that's George Zimmerman's voice. Interesting stuff though. We're going to take a quick --


HOSTIN: Exactly.

COSTELLO: Yes we're going to take a quick break. We'll continue to monitor this for you. We'll be back.


COSTELLO: Ok there was a last question from -- from the prosecuting attorney to Dr. Nakasone. He says "The people who can best identify voices are people who know the person intimately" and Doctor agreed with that. Might be logical but could be important in this case. The Doctor is now about to be cross-examined by the defense. Let's listen.


UNIDENTIFIED MALE: This is defendant's Exhibit FF for identification.


DON WEST, ZIMMERMAN DEFENSE ATTORNEY: Are you familiar with that?

DR. HIROTAKA NAKASONE, VOICE ANALYSIS EXPERT: Yes, this is my curriculum vitae.

WEST: In addition to the training and experience that you talked about a moment ago, does this contain references to your publication and research and other life experience as a voice expert?

NAKASONE: Yes. This lists my professional affiliation. I have about half a dozen of memberships in the technical associations. And also this lists the award that I received in the past including FBI Director's Award for the development of automated speaker recognition system and it also lists the -- my current effort in establishing a scientific working group for forensic and investigatory voice speaker recognition. And that scientific working group was formed and launched and kicked off on March 19th of this year and there are somewhere around 30 to 40 members among those 16 members from, they are voting members and the remaining advisory members and both of those memberships are made up of highly reputable scientists both in forensic and in technical field mostly coming from either U.S. government, federal state and also academia and major industry who produces speaker recognition technology. And --


WEST: Let's talk about that for -- for just a moment. That's the -- the working group that you mentioned in you are direction examination that you're focusing on now is a group of scientists teach through voice identification, voice comparison experts that have pulled together to meet regularly in the issue of speech or speaker identification?

NAKASONE: That is correct.

WEST: How was the group started and what is its primary mission?

NAKASONE: The concept of this scientific working group was born in 2009 when the interagency symposium was held and we recognized that there are lack -- lack of, you know, consensus or integrated or coordinated efforts in establishing a common standard operating procedures and it took about three or four years --


COSTELLO: All right because Dr. Nakasone is again going through his credentials, we're going to again take a break. We'll be back with more in the NEWSROOM.


COSTELLO: All right, somewhat unbelievably, Dr. Nakasone that FBI voice analyst, is still going through his credentials on cross. And we're -- we're curious about that shall we say because according to an "Orlando Sentinel" reporter who is inside the courtroom, jurors are yawning now. They are bored with his testimony they don't seem to get where this is going.

And neither does my panel of experts, Sunny Hostin is a former prosecutor she's out there in Sanford; Page Pate a defense attorney; Jason Johnson, a court observer. Sunny, you kind of found some reason to go through all of this so tell us more. I mean what's the point of this?

HOSTIN: Well, I think I found the reason. Based on what he said during -- during his testimony as sort of a very last piece which was familiarity -- familiar voice recognition is reliable.

So familiarity that someone could have with another person, having had (inaudible) person sort of experience stress, experience happiness, experience sadness. And so my view in this is that this witness is the setup to queue up one of the Trayvon Martin family members to get on the witness stand and say, I have you know, I knew Trayvon my entire life or his entire life. I've seen him happy. I've seen him sad. I've heard him under stress. That was his voice.

I mean when you have an expert witness Carol get on the witness stand and say "The best identification is someone who is familiar with someone else's voice, I mean that's pretty significant.

COSTELLO: All right. Well let's go to Page Pate, 30 more second then I've to take a break, so Page, a smart move in the end or? I mean the jurors are yawning.

PATE: Right. But Sunny is right. You have to set up your witnesses later in the case. So perhaps this witness will lay a foundation for another person to comment and make a point and it's helpful to the prosecution.

But the cross examination of this witness to me seems very odd. You've got him on cross, don't go through his credentials over and over and again summarize them. The jury knows this person is qualified, and then make your point.

COSTELLO: Well I guess that be a good way to discount a family member of Trayvon Martin who will say that's Trayvon Martin's voice on the tape. And then they can go back and say, yes, but it's unreliable.

PATE: Well, that's true. But a lot of this is common sense. I mean we were all discussing the fact that if you know someone, you're more like to recognize their voice than some expert is going to.

COSTELLO: That's true. I've got to take a break. We're going to be back with more after this. .


COSTELLO: Good morning. I'm Carol Costello, thank you so much for joining us. We've hit the top of the hour so welcome to NEWSROOM.

We're covering the George Zimmerman murder trial, of course, in its entirety. You are about to hear live testimony from Dr. Nakasone. He's an FBI voice analyst. He testified that there is no way that he can determine as a voice analyst whose tape was screaming on that 911 call.