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. the_dude

    Ummmm I downloaded this app for my iphone that makes peoples voices sound funny. I guess I am an expert with voice forensics as well.

    April 3, 2012 at 1:09 pm | Report abuse |
  2. Darth Cheney

    The last word a man speaks before firing a gun at close range is rarely, "Help!" That's sort of the whole point of guns.

    April 3, 2012 at 1:36 pm | Report abuse |
    • banasy©

      I know, right?

      April 3, 2012 at 1:44 pm | Report abuse |
    • Ed

      But a man that is being beaten probably would call for help AND then shoot as a last resort. Wait for the facts and evidence – "gussing" what really happened doesn't serve any purpose.

      April 3, 2012 at 1:49 pm | Report abuse |
    • The truth

      You are exactly right. However, the assumption was made by the media that the person crying for help just before the gunshot was the person crying for help throughout the entire tape. Also, the assumption has been made that we would hear all cries for help on that tape.

      April 3, 2012 at 3:23 pm | Report abuse |
    • Candy

      I understood the young man was trying to take the gun from Zimmerman . Yes and he probably yelled help not wanting to kill him or be killed himself.

      April 4, 2012 at 2:19 pm | Report abuse |
  3. Dr. Hemlock

    There will be no mistaking Zimmerman's next scream for help! May it be long and painful before it fades into silence.

    April 3, 2012 at 1:37 pm | Report abuse |
    • Zooie

      The same back to you. Idiot!

      April 3, 2012 at 2:18 pm | Report abuse |
  4. Scenario_Guy

    scenario 1 : Zimm followed martin, martin just ran and did nothing, zimm finally got hold of him and confronted martin and attacked him , martin yelled for help, zimm then killed him.

    scenario 2: Zimm followed martin, was returning back to his car, martin came back and attacked Zimm, Zimm fell to ground, zimm yelled for help and finally defended himself

    scenario 3 : Zimm followed martin, martin confronted zimm asking why are you following me, zimm in return attacked martin , martin yelled for help, zimm finally killed him.

    which one is most plausible!!!

    April 3, 2012 at 1:47 pm | Report abuse |
    • Kerry

      God and Zimmerman are the only ones who know for sure. Since Zimmerman would say anything to save his skin, not likely we can take his word for it.

      April 3, 2012 at 2:12 pm | Report abuse |
    • davidburish

      SC #4- : Zimm followed martin, martin confronted zimm asking why are you following me, martin doesn't like what he hears and attacks Zimm. Zimm , martin sees gun yelled for help, zimm kills Martain.

      SC#5 there is multi exchanges martin wins some Zimm wins some. the exchanges escalate until the gun comes out and Martin is dead.

      I would bet # 5 is near the truth.

      April 3, 2012 at 2:27 pm | Report abuse |
  5. FoFo

    Can the race of the people be put aside and deal with the case as two human beeings, the shooter would be judged based only on the evidence

    April 3, 2012 at 1:52 pm | Report abuse |
  6. John Schwendler

    Our media's primary job is to report the news, not be part of it. I just have this personal perception, this feeling that our national media have stirred this tragic story into far more than what it is. The good part of that, however, is that it has Americans talking about race, again.
    When that can be done without violence, with common sense, maturity, and reason, we will begin to make progress on American race relations among all groups. I personally don't like the signs asking for justice for just one involved person. I also personally don't like a couple of alleged men of the cloth using someone's personal horror of a tragedy for their personal needs or gain. As is quite clear at this point, the investigation is not complete. Hopefully all of this will end up in the lap of a grand jury, made up of community members, who eventually will have to sort all this out. In the meantime, Floridians should be all over their representatives to eliminate, overhaul, re-write the law in question that to me seems to be behind this mess. What we do not need, when an eventual final decision is made, is for anyone to go rioting in the streets, burning this, and overturning that, and hitting each other. That activity accomplishes nothing.

    April 3, 2012 at 2:11 pm | Report abuse |
  7. Jim

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

    April 3, 2012 at 2:15 pm | Report abuse |
    • Rebecca Ore

      Zimmerman is not a credible witness for the defense. Martin's girl friend is not particularly a credible witness for the prosecution. What is useful is the time stamps of her call with Martin and the 911 calls. If there's no time between her call and the 911 call for a beating, then Zimmerman's story looks a bit crap. Real time stamps on real phone calls (regardless of the contents) might be useful. If there's only a 30 second pause between the call with the girlfriend and the 911 recording of the shooting, then that's different than if there was a five minute pause. The length of the pause between calls should be interesting to the people investigating this.

      I also don't trust cops to not cover for a friend of the family. They were guessing that Martin would prove to have drugs in his system (he didn't) and would have a criminal or juvenile record (being suspended from school isn't a criminal or juvenile record). Zimmerman was the one who'd been arrested for hitting a police officer.

      White kids often get charges dropped for completing an anger management class or behaving themselves for a year (I witnessed this in a NYC night court - pot charges suspended pending good behavior). I think the idea is that the courts shouldn't ruin a good kid's life because of something stupid he did at 15 or 19 or 20. Thing is kids from good families who break bad are much more likely to stay bad than kids from problematic families. The mercy should be shown the other way around.

      On the jewelry and screwdriver - oh, please. A screwdriver has so many other uses than burglary. The jewelry wasn't proven to be stolen, or even real jewelry. Some school guard sounds a bit officious.

      April 3, 2012 at 2:35 pm | Report abuse |
    • Ol' Yeller

      OMG! Columbo!?! Is it really you? Your brilliance has once again solved the crime. Why couldn't we have seen the logic of this from the beginning?

      April 3, 2012 at 2:46 pm | Report abuse |
    • ladydi

      that dont prove squat

      April 3, 2012 at 2:52 pm | Report abuse |
    • Candy

      I do think you are correct. I do remember that was reported to the police he was asking for help because the kid was trying to take his gun.

      April 4, 2012 at 2:20 pm | Report abuse |
  8. daveinla

    Video evidence much more compelling. I think if Zimmerman's head were being bashed in, it was he who screamed for help.

    April 3, 2012 at 2:17 pm | Report abuse |
  9. crookedarm

    Everyone knows what's going to happen if Zimmerman isn't charged with the killing. One has to only look back at the Rodney KIing verdict to figure that one out. I wonder why there was no killing, rioting, and looting when OJ was found not guilty?

    April 3, 2012 at 2:21 pm | Report abuse |
    • Dott

      Because white people do not have a JUNGLE MENTALITY!!

      April 3, 2012 at 2:27 pm | Report abuse |
  10. Marlin

    I have no idea on this one. Im surprised that peopel still rush to judge after the Duke Lacross scandal...but I can kinda see some reasons why.

    I think that even if Zimmerman was defending himself, he still did wrong in profiling the kid and going after him. I think that we can all agree that if Zimmerman had just left the kid alone and didnt START something.. that kid would still be alive.

    1 Zimmerman Starts Something
    2 ??????
    3 Martin dies.

    That 2 is the crucical bit. Also the voice recognition thing has me leary because for each person that says it wasnt Zimmerman or that it was Martin, another is saying you cant be sure.

    Anyone remember Mr. Smith goes to Washington and the handwriting analysis?

    April 3, 2012 at 2:23 pm | Report abuse |
    • robert

      Define "start something". Following from a distance isn't confrontation. It isn't clear who came up to who or who started the scuffle. In a public place, there isn't any special authority needed to ask someone a question. Evidently, both of them did so, regardless.

      I'll wait to see what facts actually come out – and I'm sure there's more reliable evidence than the "looks like" "might be" stuff we've hear so far. But from a legal standpoint you either have someone defending themselves during an attack or someone pulling a weapon and firing for no apparent reason. Claiming this would never have happened IF THIS or IF THAT gets us nowhere. The crucial issue is what actually happened during that brief timespan.

      April 3, 2012 at 3:38 pm | Report abuse |
  11. Dott

    This is so sad that people are seeing this through color of skin eyes not facts. This proves to me that our nation will never be one. Just like the young blacks who cheered as O.J. got off without a charge for killing the two white people. However, Karma has a way of "getting You". Where is O.J. today? In prison where he should have been. So if Zimmerman did kill in self defence he will be set free. If not watch out for Karma. Plus all you people who are jumping to conclusion because of color of skin has a little Karma coming to you.

    April 3, 2012 at 2:25 pm | Report abuse |
    • Ol' Yeller

      @ Dott- Really!?! In one post you talk about Karma and how it is, "...so sad that people are seeing this through color of skin eyes not facts." And how, "all you people who are jumping to conclusion because of color of skin has a little Karma coming to you."
      But before that you posted:
      "Because white people do not have a JUNGLE MENTALITY!!"
      You'd better watch out for your own karma, I'd think.

      April 3, 2012 at 3:28 pm | Report abuse |
  12. Anon

    CNN, FoxNEWS, MSNBC, all of these NEWS sources have agenda's and hype up the public to sell more papers. And all they are selling is speculation, they don’t have all the evidence and reports. “Zimmerman shouldn’t have done this, Martin should’ve have done that, Zimmerman’s history is this, Martin’s history is that, our 4th psychic reading says a Chinese guy shot Martin and framed Zimmerman!” Bottom line is that both Zimmerman & Martin made mistakes that unfortunately Treyvon paid for it with his life. Just listening to Zimmerman’s call to the police before the incident occurred, I don't think it was Zimmerman's intention to kill anyone, and I really don't believe it was racially motivated. Everyone else just wants it to be more than what it is, a tragedy....

    April 3, 2012 at 2:33 pm | Report abuse |
  13. Lila

    That voice sounds really high like a teen, but it doesn't really matter does it? The fact is Zimmerman pursued Martin, it's in his own words on his 911 call to to the dispatchers. He was the aggressor, Martin was fighting some crazy guy. I have no sympathy for Zimmerman in any of this, he created the situation and needs to be held accountable.

    April 3, 2012 at 2:46 pm | Report abuse |
  14. Juanita Washington

    What did the officer throw in the truck of the police car on the video display of Zimmerman, who showed no obvious signs of a brawl? Did anyone question that? EVIDENCE MAYBE!!!

    April 3, 2012 at 2:54 pm | Report abuse |
  15. Ol' Yeller

    Zimmerman should just fess up and admit he stalked and killed Trayvon in cold blood. At best he would offered a lucrative high paying job on the Santorum campaign, at worst he'd get his own hour just outside of prime time on FOX.

    April 3, 2012 at 3:43 pm | Report abuse |
    • elle

      That was so funny. tx

      April 3, 2012 at 9:27 pm | Report abuse |
    • Seth

      And if, on the other hand, Trayvon had beaten Zimmermon to death that night, would he now be subjected to the same lynch mob who goes after Zim daily with no interest in the facts or the truth? For those who say it wasn't necessary to kill that child, if you are getting your head pounded on concrete, what exactly are the options? Maybe some of you should put yourself in that situation, think about it and TRY to be honest with yourself. Sometimes we have to make choices and do things we really don't want to do but, as human beings, we all share the instinct of survival; we want to live That's why the human race still exists.

      April 4, 2012 at 11:33 am | Report abuse |
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