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. Jim_34

    When the police arrived at the scene, Zimmerman told the cops that he yelled for help but no one came. So that proves that he was the one screaming on the 911 recording.

    April 3, 2012 at 4:55 am | Report abuse |
    • Kerry

      Zimmerman's account proves nothing.

      April 3, 2012 at 7:16 am | Report abuse |
    • Jackie

      yeah right....that just proves everything huh??? Listen to the tape moron, you can hear a kid screaming and then gunshot. Now if he had really been screaming, then he would have been the one shot, not Martin ....how about waiting till they test the prints on the gun, cause I lay odds that Martins prints are not on it, and IF they are, I bet experts can prove by the grip pattern, that it was placed there posthumously.....come on people, George Zimmerman is only digging himself a deeper hole, he does not want anyone to know he did wrong, especially since he the son of a "retired judge", go figure....give Zimmerman a lie-detector test....oh and how about asking the family if they have any family videos with Martins voice on them to use for comparison.....

      April 3, 2012 at 11:50 am | Report abuse |
  2. kamanakapu

    Anyone know how many feet Z's truck was from the scene of the hit? And where, exactly, did the alleged head-pounding occur? On the sidewalk? or on the grass? One of the witnesses seemed to indicate that both males were on the grass.

    April 3, 2012 at 5:00 am | Report abuse |
  3. chuckgoolsby

    I have never seen so many people, both in the press and in public comment threads, smooth-over evidence that George Zimmerman may possibly be lying.

    Specifically, despite the fact that two of America's expert voice analysts have declared that the 911 "crying" tape does not include any screams from George Zimmerman (pending more detailed analysis), both the press and many in the public refuse to even entertain the idea that this analysis could be true.

    Beyond the expert analysis, I ask that everyone who reads this just listen to the cries.

    One of the eyewitnesses reports hearing cries for help, the last of which was "painful."

    Treyvon Martin's family has declared from the time that they first heard the 911 crying tape that it was Treyvon's voice. His mother, his father and one of his cousins have all appeared on CNN and/or HLN news interview segments and declared their certainty that it was Treyvon who was crying for help.

    For those of you who are parents, would you know the sound of your child's voice on such a recording? I think that we would all say yes.

    George Zimmerman's brother has also stated, during an interview on CNN, that the cries for help were from his brother George.

    One of the forensic audio analysts who studied the 911 crying tape declared on CNN on the morning of April 2nd that he would stake his professional repution on the fact that the voice crying for help was not that of George ZImmerman. He also stated that the voice was that of a "young man."

    When I listen to the cries for help, I heard the voice of a very young man. I am incredulous when I hear so many voices discount the observations of the family, of two audio experts and of common sense, to support Zimmerman's 'official' statement of the events of the night of the shooting.

    I ask the public and reporters to consider the two most likely scenarios in regard to how events played-out that night, during the time of the recorded cries for help.
    Scenario 1 (based on Zimmerman's account)

    1. Martin comes up from behind Zimmerman, and pummels him, banging his head into the sidewalk, causing head injuries.

    2. Martin punches Zimmerman in the nose with his fist, breaking it, and decks Zimmerman.

    3. Zimmerman yells for help, and those cries are picked-up on the 911 call of the blonde woman who lives adjacent to the scene of the conflict (she has said that her window was open).

    4. The blonde neighbor and her Latina woman friend walk outside, and see Zimmerman sitting on Martin's back on the ground, and ask Zimmerman three times what was going on.

    Here is my problem with the above scenario...

    I have to ask – at what point in time was George Zimmerman so afraid for his life that he lets out desperate, urgent and painful cries for help?

    Given that Zimmerman had access to a loaded semi-automatic handgun in his pocket, I find it even more difficult to accept a theory that says that Zimmerman reached a point at which he felt compelled to plead at the top of his voice for urgent assistance from anybody within earshot.

    When Zimmerman's father, a retired judge, was interviewed by the press recently, the reporter asked him why, if Trayvon Martin was telling him the "you are going to die tonight" in addition to other threats, why are those threats not recorded on the 911 crying tape call?

    Last, Martin's family members, and most notably a cousin interviewed on HLN on April 1st, have all said that Martin was not an aggressive person, making them feel incredulous that anyone could formulate a theory that Martin circled around the complex and attached Zimmerman from behind.

    Scenario 2 (based on an alternative theory that Martin was crying for help)

    1. Martin calls his girlfriend to report that a complete stranger was following him.

    2. Martin's girlfriend tells him to run, but Martin decides to walk back toward his future step-mother's residence after buying skittles and iced tea at the local 7-11 store.

    3. Zimmerman comes up to Martin and challenges him in regard to why he was there, a statement from Zimmerman that Martin's girlfriend heard over Martin's open cell phone line.

    4. Martin's girlfriend hears the phone being knocked to the ground, and the line goes dead.

    5. Under this scenario, let us suppose that, consistent with a known history of past overreactions by Zimmerman – including a scuffle with police officers several years ago, Zimmerman, an in-shape 28-year-old man with aspirations to become a police officer (with, perhaps, the accompanying physical training), knocks Treyvon Martin to the ground, and pulls out his 9 millimeter pistol and points it at Martin.

    If any of us who are adults could think back to when we were age 17, what would our reaction have been to being shaken out of our sheltered personal reality by being stalked, chased, knocked to the ground and then being immediately faced with having a loaded gun thrust in our face by a complete stranger whose intentions are unknown?
    Our reaction would have been to scream bloody murder for help at the top of our lungs.

    From my perspective, that is the intensely fearful and painful series of cries for help that we hear on the 911 crying tape.

    As the one forensic audio expert said, 'that is the voice of a young man.'

    Under scenario #1 above, George Zimmerman was never in such fear of his life that he would have felt compelled to cry out bloody murder for help. Not with a loaded pistol within easy reach in his pocket.

    Put differently, why would Zimmerman cry out in utter desperation if he had a powerful weapon on him?
    Under scenario 2 above, Treyvon Martin would certainly, as an underage youth who was minding his own business, have felt that his life was in immediate danger, given that he was being assaulted by a complete stranger who was pointing a gun at him in a position that perhaps told Martin that Zimmerman was at the point of shooting him (murdering him).

    Mmany Americans are willing to swallow, lock, stock and barrel, a narrative by George Zimmerman that declares that 17-year-old Treyvon Martin was a violent, aggressive individual. It is a self serving accusation.

    In reality, it is Zimmerman who has a history of scuffling with police officers and of committing acts of domestic violence.

    If I had been Zimmerman, I would have walked to a dark area of the community and banged my own head against the concrete of a walkway in the minutes before police arrived.

    If Treyvon Martin was beating George Zimmerman so severely that ZImmerman had to cry bloody murder in desperation, and then had to shoot Martin as Martin loomed directly over him, then the following should be true and demonstrable facts...

    1. Zimmerman should have blood spatter from shooting up at Martin, as Martin supposedly pummeled Zimmerman from above Zimmerman's prone position on the ground.

    2. The blood spatter from Martin's gunshot wound to the chest at close range should have caused a blowback of blood onto the clothing of George Zimmerman.

    3. Martin's body would be slumped over Zimmerman at the end of the fight.

    4. Martin would have bruising on his knuckles from having punched Zimmerman,

    In reality, the funeral director who handled the preparation of Martin's body observed "no signs of a fight." Specifically, he said that no bruises existed on Martin's knuckles. (If this point is in dispute, exhumation of Martin may be the only way to prove the facts.)

    In reality, the blonde woman an her Latina friend who called police in the '911 crying tape' have declared the following in several face-to-face interviews with CNN reporters:

    1. They heard no noise from a fight prior to the shooting.

    2. They believe that the cries for help with Martin's because the cries stopped immediately after the gunshot was heard.

    3. They both walked outside and saw Zimmerman straddling Martin's body (sitting on Martin's back) in the period immediately after the gunshot was heard.

    4. They have both declared that they believe that Zimmerman did not act in self defense.

    5. They saw no signs that Zimmerman tried to help Martin after the shooting.

    Although Zimmerman's defensive legal strategy may be to cast enough doubt so that he is never found guilty in a criminal prosecution, his narrative does not pass the smell test.

    My conclusion is that the blood curdling cries for help heard on the 911 tape belong to Treyvon Martin.

    It is clear as a bell to me that the voice is of a youth, not an adult man.

    It is also clear that the person crying for help is in immediate fear of imminent death.

    As Martin's parents stated to the press after hearing the 911 crying tape for the first time, Treyvon knew that he was facing his own death.

    Listen to the tape, and be honest with yourselves.

    I especially ask this of those professional reporters who continually seek to put a pro-Zimmerman spin on this powerful audio evidence.

    April 3, 2012 at 5:18 am | Report abuse |
    • ladydi

      Aaahhh...................your comments are as long as "War and Peace"...........enough. Keep it simple.

      April 3, 2012 at 7:26 am | Report abuse |
    • Sam

      Another arm chair investigator that has ALL the answers. You are a complete tool shut up and wait for the REAL investigators to do there job.

      April 3, 2012 at 7:39 am | Report abuse |
    • Jimmy


      April 3, 2012 at 7:54 am | Report abuse |
    • Oakspar

      1) A phone call that records cries for help in the background is not going to record normal conversation or the sounds of struggle of people far away.
      2) Phone analysis that shows a 48% likelihood that it is Zimmerman based on poor control samples to compare. Did they do a similar sound study to show a higher likelihood that it was Martin instead? If so, you would think that would be in the article.
      3) If you shoot someone dead who is on top of you, then roll over, you end up on top of them. What is surprising is not that Z was on top by the time witnesses arived, but that they arrived so quickly that he had not yet gotten up.
      4) Z did not pull his gun and shoot Martin down. They were in a physical altercation. That meant that either Martin approached Z or allowed himself to be approached by Z. Martin was clearly faster and had a head start – including giving Z the slip at one point. Martin could have chosen to run home where his father was or could have called the cops on the guy following him.
      5) Any testemony not given to police on that night is highly suspect, due to the nature of the medial coverage and community outrage. If you had watched the entire thing go down entirely as Z had said, would you come forward? Knowing that there would be death threats, everyone would call you a liar, knowing you would have to flee your home, job, and community? (I'm not saying there is such a person, I am arguing that all testemony give to the media from both sides is highly suspect).

      The simple truth is that two imperfect and flawed people collided with fatally tragic results and both lives were ruined. Z should have not followed. M should not have had pot at school (or the leftover bag) to get suspended and be at his dad's instead of going to school from his mom's. Z should have drawn down ealier so that no physical altercation could have begun (I assume M would not charge a man holding a gun). M should have run straight home, or better yet, not been out so late at night – far too late for any teen to be out without a clear purpose (returning from a job).

      They were both guilty of several bad judgement calls. There is no question that neither of them did right or acted wisely. The only question is which one was technically commiting a crime of assault (and if it was Z, the subsequent crime of murder).

      It amazes me that so many sensible adults have chosen sides so dramatically in an oversized case of "who started it" when every parent of at least two children on the planet knows that they are both kids are always to blame.

      April 3, 2012 at 8:16 am | Report abuse |
    • CJ

      What a well thought out........farce! Regardless of who was screaming on the 911 recording, it does nothing to prove or disprove what happened. The 911 recording gives a sound, and that's it. Even if it was Trayvon screaming for help, it tells us nothing about the facts. People harping on the 911 call seem to think it proves something, when in fact.....it proves nothing! Move on to the real facts of the case.

      April 3, 2012 at 8:18 am | Report abuse |
    • Butta

      Listen to the tape and judge for ourselves? Well, considering the 911 call is indicative of nothing, we should take nothing away from it. You make it sound as if the 911 call has all the answers. Maybe you should re-evaluate the true significance of the recording. Then, you might be able to be a little more objective. Good luck with your 911 recording book.

      April 3, 2012 at 8:24 am | Report abuse |
    • Jim

      In all the coverage, I have yet to hear one pro zimmerman spin on this case.
      It's shameful.
      The coverage has been biased since the very beginning.
      The media made up it's mind to attack George Zimmerman as soon as the story broke.....without hearing a shred of evidence.
      Just shameful.

      April 3, 2012 at 9:03 am | Report abuse |
  4. ricksok

    The Zimmerman narrative keeps changing. First they said he nearly lost consciousness, had a bloody gash on the back of his head and a broken nose. Now, apparently he regained his wits enough to be handcuffed, had a bump on his head and if he had a broken nose where are the photos showing discoloration around the eyes and nasal area that occur frequently when someone has their nose broken?

    April 3, 2012 at 6:37 am | Report abuse |
    • Lssade12

      It usually takes 24-48 hours for discoloration to appear and bruising to set in and the video was taken shortly after the incident, but you already know this pesky little fact I'm sure. But, hey, throw it out and question it like you don't know to mislead and support your biased opinion.

      April 3, 2012 at 6:45 am | Report abuse |
    • Sam

      This is an ongoing investigation and the police are under no obligation to show you or anyone else the evidence until the investigation is done. What is wrong with you?

      April 3, 2012 at 7:37 am | Report abuse |
    • CheckptCharlie

      Again, the video really shows us nothing. Better yet, it shows what the media wants you to see. The first video appeared to show Zimmerman with no injuries. The second video released clearly shows gashes on the back of Zimmerman's head (not bumps). So, this tells us that a few seconds of video can be slanted any way the media wants it. In regards to the broken nose, it usually does not get inflamed or show bruising until many hours AFTER getting broken. So, again, the video tells us nothing about a broken nose.

      April 3, 2012 at 8:31 am | Report abuse |
    • rafee

      exactly, why weren't photos taken prior to zimmerman being cleaned up, any law enforcement agency would do that.

      April 3, 2012 at 9:39 am | Report abuse |
  5. Lssade12

    Hey chuckgoolsby, maybe America should just throw out an arrest, trial/conviction and go grab a noose and hang Zimmerman based on your "expert" findings in this case. Who cares that you're obviously biased to one version of events that you've reasoned in your mind happened. We can all play along and call it fact and get us some vigilante justice. It's the American way, right? Guilty until proven innocent...

    April 3, 2012 at 6:39 am | Report abuse |
  6. ricksok

    It's been 36 days. Where are the photos of MR. Z's black eyes?

    April 3, 2012 at 6:50 am | Report abuse |
    • Lssade12

      With those conducting the investigation and with those preparing for a possible trial, where it should be. In a murder investigation those pictures would exist. I guess just because the media hasn't gotten their hands on them yet means it didn't happen, right? Never mind that his injuries are listed by the initial police reports and that the fire department paramedics that arrived at the scene were referenced as treating those injuries.

      April 3, 2012 at 7:01 am | Report abuse |
    • Sam

      This is an active and ongoing investigation. The police are under no obligation to show YOU or anyone else evidence while this is still an active case. Sorry this is not a trail by media.

      April 3, 2012 at 7:43 am | Report abuse |
  7. jerry


    April 3, 2012 at 6:57 am | Report abuse |
  8. Eric

    Now cnn wants to do some real reporting on this issue???? IDIOTS!!!!!!!

    April 3, 2012 at 7:01 am | Report abuse |
  9. vicki wright

    I want to know why CNN is not looking into the case where the 17 y/o who was shot and the man almost beat to death in his car..Are these Hate crimes.Was the white man who was beat with a hammer in his own car by two afro-americans a victum of a hate crime. Ther are other crimes in Sanford Fla to report on.

    April 3, 2012 at 7:49 am | Report abuse |
  10. robert

    In my neighborhood, we do not have crime watch. If a neighborhood activates crime watch, their must be a serious problem. Crime watch volunteers are calling 911 – 50 plus times, this neighborhood is much more dangerous than any neighborhood I have lived in or any neighborhood, I am aware of. My children teenagers are not allowed to hang out in my neighborhood unless they are passing through to a destination.

    April 3, 2012 at 7:59 am | Report abuse |
    • Dave

      I think its great that they are contemplating protests against the local shop owners in Sanford by boycotting their stores until Zimmerman is arrested. How long can Mom and Pop stores afford to lose? It's great! After all, it business taxes paying Sanford Police salaries. In Memphis, they cut the police officer salaries and the police substanially reduced writing tickets costing the city millions in lost revenue. It's great what people can do if they unite!

      April 3, 2012 at 8:53 am | Report abuse |
  11. Phoenix

    There were 2 people involved, 1 of them screamed. By my math there is a 50% chance it was Zimmerman and a 50% chance it was Martin. I'm so glad we have an "EXPERT" who can give us an opinion about who it was! I mean what would we do without the 40% it was Zimmerman "EXPERT" opinion? 40/60 vs 50/50 hmmmmm....how about just flipping a coin guys?..Well at least CNN is now using a picture of 17 yr old Martin instead of the 14 yr old Martin(I mean what they couldn't dig up any pictures of this kid as a toddler?!)! And they are now acknowledging Zimmerman is Hispanic and not "White". Should I now believe CNN reporting this story unbiased? ....Nah!

    April 3, 2012 at 8:01 am | Report abuse |
  12. Phoenix

    Well here is my opinion: Only cowards carry guns to begin with because it makes them feel all powerful and important. So I would bet a quarter it was Zimmerman yelling like girrrlly. Then I would flip the quarter to figure out who was screaming! Odds are 50/50 I would get the right one!

    April 3, 2012 at 8:13 am | Report abuse |
  13. sweetpea

    @chuckgoolsby- I agree!!!

    April 3, 2012 at 8:33 am | Report abuse |
  14. Dave

    What does this case say for domestic violence? As long as there are no witnesses, you can kill your spouse if you feel threatened. Stand Your Ground. And that goes both ways. Women can shoot abusive husbands and husbands can shoot wives for slapping them. If in doubt, just break your own nose and blame it on your spouse. That's all the justification you need.

    April 3, 2012 at 8:47 am | Report abuse |
  15. kurtinco

    We don't need an audio expert to tell us that was the voice of a 17 year old boy pleading for help that would never come in the last seconds before his murder. I hope Zimmerman gets what he deserves for the murder of this boy.

    April 3, 2012 at 8:49 am | Report abuse |
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