April 2nd, 2012
05:27 PM ET

Analysts: Questions surround 911 call analysis in Trayvon Martin case

Two experts who analyzed a 911 call made during the confrontation that ended in Florida teenager Trayvon Martin's death said they believe the screams heard in the background are not those of shooter George Zimmerman.

Zimmerman, 28, has claimed self-defense in shooting Martin on February 26. He said the 17-year-old accosted him after he called police to report Martin as a suspicious person walking around his neighborhood.

But the analysis poses some questions, legal analysts say, including whether it would be ruled admissible in court if charges are filed and the case goes to trial.

Audio experts Tom Owen and Ed Primeau analyzed the recordings for the Orlando Sentinel, and both said they believed it was not Zimmerman screaming.

"There's a huge chance that this is not Zimmerman's voice," said Primeau, a longtime audio engineer who is listed as an expert in recorded evidence by the American College of Forensic Examiners International. "As a matter of fact, after 28 years of doing this, I would put my reputation on the line and say this is not George Zimmerman screaming."

But is the analysis definitive enough for use in court? David Faigman, a professor of law at the University of California-Hastings and an expert on the admissibility of scientific evidence, said courts and the overall scientific community have mixed opinions about the reliability of such "voiceprint" analysis.

And CNN and HLN legal analysts Beth Karas and Sunny Hostin raised questions about what the public should consider regarding the conclusions reached.

Hostin says there are several questions and variables that must be considered, including the fact that the tests did not analyze similar speech. That is, the analysis was based on screams heard from a distance in a 911 call, compared with a direct phone conversation Zimmerman had with a 911 operator.

"Ideally, you want (Zimmerman or Martin's) voice saying the same exact thing, screaming 'help,' in order to analyze it," she said.

Would these tests even be admissible in court and considered evidence?

"It really depends on the individual judge," Hostin said. "In Florida, they are going to conduct a Frye test, the legal test, which asks if the science is generally accepted in the community."

Karas questioned whether the test stood up to the voice comparison standards of the American Board of Recorded Evidence, of which Owen is chairman emeritus.

 The standards indicate that when analyzing speech, there should be a minimum of at least 10 words to be compared with each other in order to say you can have a "possible elimination" conclusion. But in this case, the cries for help don't have nearly that number of words.

Owen said the published American Board of Recorded Evidence standards only partially apply to the kind of test he conducted.

"These standards apply to the older aural-spectrographic analysis and software," Owen said. "This only partially applies to the biometric software."

Both Karas and Hostin urged caution when it came to coming to a sure conclusion on the findings made by Primeau and Owen.

"I do think we need to take a step back, as with most of the facts in this case, and look at it the way the court would," Hostin said. "And that is by asking if the circumstances of how, and if, the test was done, OK, and wait to determine whether it's reliable."

– CNN's Greg Botelho and Mike Pearson contributed to this report.

soundoff (560 Responses)
  1. DoubleW

    B S! I heard those screams. That was the 17 yr old kid. Zimmerman is making this up to cover his tracks of killing the kid!

    April 2, 2012 at 5:34 pm | Report abuse |
    • Loren

      And DoubleW, you are an expert in voice analysis? And you know how to tell the difference between voices on a directly recorded call versus a call recorded over the 911 operators headset? And how much did you make last year doing this voice analysis? Or can you tell it was Trayvon Martin because blacks scream in a certain distinct way versus how Hispanics scream? You, sir, are an ass.

      April 2, 2012 at 5:49 pm | Report abuse |
    • WestVA

      Yeah, he's covering up his tracks. That's why he told one of the neighbors to call 911 and he waited at the scene. What you are saying is the biggest load of horse crap I've ever heard.

      April 2, 2012 at 5:53 pm | Report abuse |
    • Petey Gibson

      Nah, that's definately Zimmerman yelling for help.

      April 2, 2012 at 5:59 pm | Report abuse |
    • bs

      screams of kid , so what that doesnt prove anything !
      Suppose, i come to kill you or hit you and you show me a gun and push me down hard, i will scream for sure. Now tell me does this scenario sound plausible ?

      April 2, 2012 at 6:02 pm | Report abuse |
    • SpenderH

      Zimmerman would have a reason to lie, but I don't see why the eye-witness who says he saw and heard Zimmerman on the ground yelling for help would want to lie to the police. Also, nobody has contradicted anything Zimmerman has said, other than "I think this" or "I think that" happened. If Zimmerman were making events up someone would have noticed a discrepancy and his whole story would be blown.

      April 2, 2012 at 9:24 pm | Report abuse |
    • Phoenix

      No way those were sisssy girrly screams you know it was Zimmerman.

      April 3, 2012 at 8:23 am | Report abuse |
    • ladydi

      I agree......it was a scream coming from a kid, not a full size adult male.......

      April 3, 2012 at 9:04 am | Report abuse |
  2. Christopher Spata

    What if Trayvon had killed Zimmerman instead??

    The Stand Your Ground self defense law goes two ways. I talked to a Florida law professor to get to this answer:

    http://yhoo.it/whatifTrayvonkilledZimmerman

    April 2, 2012 at 5:36 pm | Report abuse |
    • cherry

      common sense lady,do you think zimmerman will go after him if he has no gun.in the first place he was told not to follow him because trayvon ran.but you know what am just glad that trayvon box him to fracture his nose because that is self defense,he fought back because he was attacked by zimmerman,and zimmerman attacked him because he was sure he will win in the fight rest assured because he has a gun...get it...

      April 2, 2012 at 5:58 pm | Report abuse |
    • SpenderH

      Christopher Spata: I completely agree, but the problem is that NOBODY KNOWS WHO THE INITIAL AGGRESSOR IS. Zimmerman tells a story which may or may not be true, but there is ZERO EVIDENCE contradicting his story (at least that I have seen). With ZERO EVIDENCE indicating that Zimmerman may have been the initial aggressor he can not be convicted, he can not be charged, and he can not even be arrested.

      April 2, 2012 at 9:29 pm | Report abuse |
  3. DoubleW

    Opps, read that first paragraph wrong. Yep! Zimmerman gonna hafta PROVE self defense, in this case the state doesn't have to do very much.

    April 2, 2012 at 5:37 pm | Report abuse |
    • WestVA

      Again, uneducated comment. Zimmerman doesn't have to prove anything; it is the state that bears the "beyond a resonable doubt" duty. All Zimmerman's attorney has to do it put doubt in any of the jury's mind and they win.

      April 2, 2012 at 5:57 pm | Report abuse |
    • Say it ain't so

      I understand if you read one word wrong or even one sentence... How can you read an entire CNN column wrong??? Is beyond me.

      April 2, 2012 at 6:09 pm | Report abuse |
  4. cameo35

    ........yup sounds like zimmerman..........................

    April 2, 2012 at 5:49 pm | Report abuse |
  5. beezy

    while this is a trajedy i am sick of hearing about it already. we will never know the truth and even if we did people will call it a cover up.

    April 2, 2012 at 5:50 pm | Report abuse |
  6. JoJo

    The BS is the media anylizing audio and video. Then releasing results to the public to sell papers. This is not evidence, the experts have not been recognized by the courts. The media is just jeopardizing a fair trial. Its absurd and irresponsible.

    April 2, 2012 at 5:51 pm | Report abuse |
  7. yoshiknows

    this voice thing really does not matter – even if Zimmerman said a racial slur – you still cannot attack him and that is why Trayvon is dead. Shame on all these news stations try to dig this up, and NBC should fire everybody for manipulating the recording – that's a sin!

    April 2, 2012 at 5:53 pm | Report abuse |
    • dave

      It is against the law to racial profile.If there was an "attack " as you call it, some would say self defense, then it was provoked by someone who aggressively profiled.

      April 2, 2012 at 6:04 pm | Report abuse |
  8. clinky

    I am figuring that since Owen is chairman emeritus, he is not going to stake his good reputation on a flimsy claim. It is reasonable to think he has substantial evidence. I am wondering if independent vocal recordings of Trayvon will emerge, such as from any home videos laying around in his family's or friends' possession? If a good match can be made between a recording like that and the 911 screams, it would help the Martins' case a lot.

    April 2, 2012 at 5:54 pm | Report abuse |
  9. joeinalabama

    Not sure what happen, not sure if Zimmerman exceeded what he should have done, but if someone gets me down and beats on me, I'll shoot him and sort the rest out latter.

    April 2, 2012 at 5:56 pm | Report abuse |
    • cherry

      well zimmerman followed him ,and he saw that he was unarmed..how does it sound to you..is it right to kill just like that,after all zimmerman was the one who engaged the the fight,because he is confident enough he has a gun..and i were trayvon i will fight too..and glad that he had a broken nose or it is just a cover,he broke his own nose..better than going to jail and ends up in electric chair..

      April 2, 2012 at 6:13 pm | Report abuse |
  10. bccream

    It is unbelievable that someone screams help help and then shoots, I am sorry but this is beyond common sense. Unless Martin got hold of Zimmerman's gun and then Zimmerman after screaming help help got hold of it back, there is no way it was Zimmerman who was screaming, unless of course he was a psychopath.

    April 2, 2012 at 5:56 pm | Report abuse |
    • ton

      What? How would it be unbelievable that someone would be screaming for help before shooting? What, you'd go straight to shooting before screaming for help? YOU sound like a psychopath.

      April 2, 2012 at 6:02 pm | Report abuse |
    • Guest

      Worst logic ever. How is is so far fetched that Martin was on top of him beating him, he screams for help, no one comes and so he pulls the gun. Now I'm not saying that's what happened because I have no clue. But neither do you. So quit trying to lynch this person until the actual facts come to light. All your speculating and idiotic logic is only fueling a fire that doesn't need stirred at this point.

      April 2, 2012 at 7:20 pm | Report abuse |
    • chuckgoolsby

      I agree. It is implausible that Zimmerman, carryinh a loaded pistol, would scream at the top of his lungs for help.

      The voice is a very young voice in the recording. It is the voice of someone staring down the barrel of a gun.

      Trayvon Marting was crying for help, for his very life.

      April 3, 2012 at 5:45 am | Report abuse |
    • frespech

      BC & Cherry- Go get an education and then come back and comment, maybe somewhat intelligently.

      April 4, 2012 at 4:47 pm | Report abuse |
  11. Vern

    What is happening in the world that so much time and media attention is being spent on this. Something going wrong in one of the many wars? How about North Korea, all's well. Foxxconn kill a few hundred Chinese? Iran been invaded and we are stuck on a shooting in Fl? Just wondering

    April 2, 2012 at 5:58 pm | Report abuse |
  12. jwarino

    the problem here could be tampering with evidence. that an independent expert looked at this and made a statement to the media in my opinion obstructs justice. if there is to be a fair trial the media really has no business conducting their own investigation. keeping the public in an uproar is counter-productive in protecting individual rights and ensuring a fair trial.

    April 2, 2012 at 5:58 pm | Report abuse |
    • chuckgoolsby

      The problem with waiting for the courts to wade the the evidence and sort it all out is that – no arrest has been made.

      Therefore, this case is being tried in the press.

      The public demands answers. There is nothing wrong with independent voice analysis.

      It is not tampering, because the evidence does not change, and can be retested a thousand times.

      April 3, 2012 at 5:49 am | Report abuse |
  13. Eloe

    The voice belongs to someone who is screaming for their life. Someone who looks death in the eye. Not someone who gets beat up by a teenager.

    April 2, 2012 at 6:02 pm | Report abuse |
    • frespech

      Tell me this genius why isn't he screaming don't shoot. Because it isn't Trayvon, it's Zimmerman

      April 4, 2012 at 4:50 pm | Report abuse |
  14. Bill

    The government witnesses, the voice experts, will ALWAYS favor the ones who sign their checks. If they didn't, they wouldn't be hired again. Same with the defense. "Experts" are no more than hired witnesses who will testify in the favor of who hired them, or not be hired again. It's a fact of American justice.

    April 2, 2012 at 6:04 pm | Report abuse |
    • jwarino

      totally agree.

      April 2, 2012 at 6:05 pm | Report abuse |
    • Eloe

      The defense can always run their own tests, but of course than one could claim they pay the witness I guess.

      April 2, 2012 at 6:11 pm | Report abuse |
    • Bill

      Eloe wrote:

      "The defense can always run their own tests, but of course than one could claim they pay the witness I guess."

      There are rules in place for what can or can not be asked. It is the duty of the attorney for the defense to present the witness in a way that doesn't open the door to such questions. Prosecutors know this and do the same. It's not about justice, but who has the lawyer with the most tricks and can get the best professional liars before the jury.

      I could hire, at a clients expense, an "expert" who would testify that the moon was made of cheese. I could do it in such a way that the prosecutor has no chance to refute it and the jury, by instruction, cannot question it, as they can only consider what has been put before them and nothing else. Only in America.

      April 2, 2012 at 6:29 pm | Report abuse |
  15. edward ryder

    its funny how those who are tired of hearing about the trayvon martin incident,just happen to be white.most whites are in denial about racism or naieve,americas history with african-americans speaks for itself.right now they are shook up because an african-american is president.this has spawned the so-called tea-party, which is just another name for the klu klux klan under the disguise of political expression.regardless of what president obama does right or wrong,like they say their goal is to get obama out of office.why? the economy is on a rebound,jobless rate has dropped and employers are hiring again,the stock market has been soaring,usama bin laden is dead, we're out of iraq,so the only thing i can see is racism.hate to see an african-american achieve anything.though we may never know the truth about trayvon martin,one thing we do know,he should have been arrested and let the courts decide one way or the other,if george zimmerman is guillty.most whites on the other hand, don't even want zimmerman to be arrested, ato ascertain the truth.double standard,i wonder if it was the other way around that you people who keep trying to make excuses for george zimmerman and victimize the victim trayvon martin would feel and react the same way.as an african-american,i'm tired of the self-righteous hypocrites

    April 2, 2012 at 6:04 pm | Report abuse |
    • DevilDriven

      Your race causes most of the damn violence in the country.. Clean your acts up and this crap wouldn't happen..

      April 2, 2012 at 11:04 pm | Report abuse |
    • frespech

      Edward you were doing pretty good for about 90% of your blog. I want Zimmerman arrested if the State thinks they can prove his guilt. That is the way the system works. Many cases are never brought to trial and some are brought to trial 5 years after the crime was committed. Lets just see how it turns out. Sad but true but us whites can never no the black experience and vice versa. When it is an equal experience then freedom will finally be recognized.Have a good day.

      April 4, 2012 at 5:00 pm | Report abuse |
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