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

    Instead of a tale of two versions......it's a tale of buying two audio "experts".

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

      Z's story is after all only a story....nothing to verify....all hear say! No back up, no pictures!

      April 3, 2012 at 10:06 am | Report abuse |
  2. Dan

    The police report says Zimmerman was bleeding; are the police liars? If so what was their motive in committing a crime? Was it because Martin was black and they hate all black people and love Hispanics? What happened to the eye witness that said he saw and heard exactly what Zimmerman says happened?
    Why did Martins parents give the media a picture of their son when he was just a boy when in fact he was older and bigger than most men ever get including Zimmerman? Was it that picture that stirred every one up including the President? Where we mislead from the beginning?

    April 3, 2012 at 9:09 am | Report abuse |
    • JOSE0311USMC

      I JUST A PICTURE OF ZIMMERMAN INJURIES...IN ON AOL FRONT PAGE.....HUGE CUTS.....ZIMMERMAN LIFE WAS ON THE LINE/..........SELF DEFENSE.. POLICE MADE THE CORRECT CALL...MARTIN ATTACKED ZIMMERMAN

      April 3, 2012 at 9:31 am | Report abuse |
    • Erin

      Personally Dan, his picture has nothing to do with the fact that this case offended me.
      Step back and look at the case, without the involvement of race, and i don't think there would be a question as to why anyone is offended by this.
      Zimmerman might have used self defense, but he is alive. Trayvon is not. we will never know the intire story because the victim is dead. what about his self defense? he shouldn't have been able to punch zimmerman in the nose? if it was night and i saw someone i didn't know, (who was bigger than me) coming after me with a gun....really. do i need to continue? because Dan, i know you would have acted in self defense.

      April 3, 2012 at 9:56 am | Report abuse |
  3. steve

    those audio so called experts have finally been EXPOSED! total frauds!

    April 3, 2012 at 9:09 am | Report abuse |
    • jboh

      You lie! Go burn a cross.

      April 3, 2012 at 9:29 am | Report abuse |
    • terryrayc

      How so, nothing in this report exposed anything? These men are using science...They ran accepted tests. Now the only issue is they do not have Trayvon Martin's voice to compare it against...which seems strange, you'd think they'd have found something to use. But other then that nothing these men have done is wrong nor not correct.

      April 3, 2012 at 9:37 am | Report abuse |
  4. sortakinda

    Presented yesterday as a definite (48% guess), now CNN reports questions? Consistent with the baseless statements prsented as fact by CNN ever since it picked up this story. Mr. Zimmerman has gone from whilt hispanic/white to hispanic. What's next? Peruvian? Mayan chieftain? E.T.?

    April 3, 2012 at 9:10 am | Report abuse |
    • Logic

      That would be Incan chief (Peru), but I get your jist.

      April 3, 2012 at 9:59 am | Report abuse |
    • moving1

      You are right on point, a twist to change the story .At the end of the day one thing for sure, it is murder. I guess CNN can pick and choose what is politically correct. i bet on his job application he listed himself as white. his dad is. what CNN should so is check his dad court records and see how much black he might have sent to jail that should have been released.

      April 3, 2012 at 10:23 am | Report abuse |
  5. Amit-Atlanta-USA

    "There's a huge chance that this is not Zimmerman's voice,"- says the "SO-CALLED" expert.

    And by the expert’s own analysis that HUGE CHANCE is 52%.!!!!

    Is it not much more fair to say that the chances are pretty even that the voice may or may not be of Zimmerman given that it's a 48 to 52 chance which is almost a tie?

    And when we overlay that on the fact that Trayvon Martin’s voice has NOT even been analyzed, it makes the analysis much less dependable.

    For the simple reason if the experts can rule out say with a 80-90% accuracy that it’s NOT Trayvon Martin’s voice, then it BOOSTS the confidence that it is Zimmerman’s by almost an equal % point, viz. it’s 80% certain that it indeed is Zimmerman’s!!!

    April 3, 2012 at 9:13 am | Report abuse |
    • John

      We started out with a 50/50 guess on who was screaming. Now we're at 48/52, without the second voice being analyzed. That doesn't sound to me like we've gotten very far, especially without a second voice comparison. Seriously, nobody has a voicemail, answering machine message, or anything of this kid? It's got to be one of the two, unless it was a mysterious third party who witnessed it all and went into hiding. My guess is that when comparing somebody screaming for his or her life vs. talking regularly, you'll very rarely get a clear match.

      April 3, 2012 at 10:01 am | Report abuse |
    • perennial2

      Circus News Network geniuses don't seem to grasp – nor does their equally low IQ loyal black nationalist fan club – that it was from 2/26 a 50/50 toss up as to this voice or than on the 911 call, as there were only 2 individuals involved in the fracus.

      April 3, 2012 at 10:41 am | Report abuse |
  6. Glenn

    I'm looking forward to seeing Zimmerman on a future episode of Lockup.

    April 3, 2012 at 9:18 am | Report abuse |
    • JOSE0311USMC

      ZIMMERMAN ACTED IN SELF DEFENSE...HE HAVE HUGE INJURIES IN BACK OF HIS HEAD...HE SHOULD WALK...

      April 3, 2012 at 9:33 am | Report abuse |
    • Zooie

      Won't happen. He killed in self defense and in Florida you can protect yourself.

      April 3, 2012 at 9:48 am | Report abuse |
  7. losingatmonopoly

    Zimmerman had no reason to scream for help. He was carrying a concealed weapon the entire time and Martin wasn't.

    April 3, 2012 at 9:29 am | Report abuse |
    • JOSE0311USMC

      CARRYING A CONCEAL WEAPON IS ALLOW UNDER THE LAW, DUH....

      April 3, 2012 at 9:34 am | Report abuse |
    • JOSE0311USMC

      ZIMMERMAN I'M SURE WAS TRYING TO AVOID USING DEADLY FORCE, WHY HE WAS SCREAMING FOR HELP...A NEW VIDEO SHOT ZIMMERMAN INJURIES....HIS INJURIES GOT CLEAN AT THE SCENE ...LOOK AT THE NEW VIDEO....MARTIN HAVE NO CASE, IN SELF DEFENSE LIKE I BEEN SAYING....MARTIN I BET YOU WAS ON DRUGS..

      April 3, 2012 at 9:37 am | Report abuse |
    • terryrayc

      and it looks now like he wasn't screaming for help. how did the fight start (If there was on). You guys all want to say Martin started it, but wasn't it ZIMMERMAN who started the chase? wasn't it ZIMMERMAN who ignored the instruction of 911, wasn't it ZIMMERMAN who pulled the gun, wasn't it ZIMMERMAN who had the real power here and could have stopped this killing? THAT IS THE PROBLEM. MArtin had a right to defend himself...it was late at night and some strange man was running after him for no reason, I'd have thought I was in danger as well.

      April 3, 2012 at 9:47 am | Report abuse |
    • Kreslev

      I believe your caps lock is stuck in the on position.

      April 3, 2012 at 11:47 am | Report abuse |
  8. roe

    White people are funny. history dont mean a thing because ur daddy did it not you? We may commit alot of crime in this country but you whites commit it everywhere in the world. The man isnt even white be he should have stayed in the truck. Plain and simple. Say what you want. He dont get out the truck no one dies that night. Point blank.

    April 3, 2012 at 9:32 am | Report abuse |
    • Rita

      sorry you are so negative about the white people. Your ancestors were captured by your own people and sold to our ignorant forefathers. No one living today in America owned slaves and no one living in America was a slave. Africia different story. People such as yourself keep wrapped in a bitter shell blaming the white race for all your woes. We as a white race are getting very tired of the blame for all your problems. Think about it this way. Celebrate the fact that you are in this wonderful nation because of the ignorance of both races. You are an American and enjoy all the freedoms of this nation. You do not have to try to come here illegally. Give up the hatred it does not necessarly work both ways. I owe you nothing as you owe me nothing. Have a great life.

      April 3, 2012 at 9:44 am | Report abuse |
  9. Rita

    The family of the dead man will do everything they can to be sure that the so called white man pays for their son's death. They do not want facts. What if the young man was the one there previously breaking into the homes? If so they will never admit it. Was any testing done on the dead man to see if he was on drugs. NO At first he was going to VISIT someone in the complex and now they say he was staying there. What is the real answer? I am willing to wait until the investigation is complete before making my judgement. This is such an over reaction to a sad story.

    April 3, 2012 at 9:36 am | Report abuse |
    • terryrayc

      #1, they know he was breaking in...he just got there and the break in
      s were going on for a while. He was staying there, read the reports. The overreaction was on Mr Z's part, he ran after a boy when told not to. He pulled a gun on an unarmed boy, he profiled and was wrong. Had Mr Z followed the instructions given to him by 911 this would never have happened. You'd think after placing over 100 calls to 911 over the last few months he'd be an expect on following their directions......no what you have here is a want-ta be cop who wanted to play hero and ended up killing an unarmed boy for no reason.

      April 3, 2012 at 9:44 am | Report abuse |
    • Augutine

      Was he breaking into a home at the time of this incident? You narrow minded piece of crap.

      April 3, 2012 at 1:43 pm | Report abuse |
  10. terryrayc

    hey JOSE0311USMC, how do you know he's life was on the line? He followed Martin(When told not to) he pulled the gun out, How do you know Martin didn't feel threatened? How would you feel if some strange man was following you for no reason and even when you ran away he still ran after you. I'd have felt threaten as well...which is a good thing for Mr. Z because I carry a gun and if some man had ran after me at night for no reason I'd have pulled it out and confronted him.

    April 3, 2012 at 9:40 am | Report abuse |
  11. terryrayc

    This was a mistype

    #1, they know he was breaking in

    should have said #1, they know he was not breaking in

    April 3, 2012 at 9:48 am | Report abuse |
  12. Maintain An Even Strain

    Is this George Zimmerman or Robert Zimmerman? The question could be.. Is this Bob Dylan?

    April 3, 2012 at 10:00 am | Report abuse |
  13. losingatmonopoly

    @JOSE0311USMC: the legality of Zimmerman carrying a concealed weapon has nothing to do with it. It doesn't seem likely that the person who was carrying a loaded 9 millimeter under his jacket is the one that's going to end up screaming for help during a confrontation. Also, if it was legal for Zimmerman to carry a concealed weapon, it would have also been legal for him to display the weapon to Martin right from the start, correct?

    April 3, 2012 at 10:11 am | Report abuse |
    • JOSE0311USMC

      JUST BECAUSE ZIMMERMAN HAD A WEAPON, HE WOULD NOT BE SCREAMING FOR HELP ?? WHY NOT ? MAYBE HE WAS HOPING FOR HELP SO HE DIDN'T HAVE TO USE DEADLY FORCE.....IF A GUY IS ON TOP OF YOU BEATING YOUR FACE AND SLAMMING YOUR HEAD INTO THE CEMENT , YOU WOULD NOT CALL OUT FOR HELP TO AVOID USING DEADLY FORCE ?? I WOULD...DEADLY FORCE IS THE LAST THING YOU WANT TO USE, I BELIEVE THAT ZIMMERMAN DID JUST THAT..........THIS MORNING I SAW THE INJURIES ON ZIMMERMAN HEAD FOR THE FIRST TIME, HUGE CUTS, LIFE THREATENING INJURIES.....ZIMMERMAN WAS JUST GOING TO ASK MARTIN, WHAT ARE YOU UP TO ? HE DID NOT SHOW MARTIN HIS GUN.....SOME SAY THAT MARTIN TRIED TO TAKE ZIMMERMAN GUN ??? ALL THAT WILL COME OUT SOON.

      April 3, 2012 at 10:43 am | Report abuse |
  14. NorCalMojo

    Who's paying the experts?

    April 3, 2012 at 10:24 am | Report abuse |
    • perennial2

      Bingo! We have a winner.

      April 3, 2012 at 10:43 am | Report abuse |
  15. COJUSTICE

    "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)."

    SO LATE???????? Give me a break. 7:15 is not late, it appears someone isn't keeping up with their facts.

    April 3, 2012 at 10:43 am | Report abuse |
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