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. ronin48

    There's some real, hard scientific analysis - a "huge chance" it's not Zimmerman. What's a "huge chance" - is 50% "huge" (i.e., a coin toss)? 75%? 95%? 25%?

    Also, like the Hound of the Baskervilles, these experts' comments are significant for what they DON'T say - they don't say that it IS Martin. Don't they have samples of his voice somewhere, for example from voice-mails he left or video from his facebook page? Every teenager these days has recorded tons of stuff. Why aren't they testing that to see if it IS Martin?

    April 2, 2012 at 8:40 pm | Report abuse |
    • not_sure_if_trolling

      I think you mean "the dog [that] did nothing in the nighttime" – that's from "Silver Blaze", not "Baskervilles".

      April 2, 2012 at 8:44 pm | Report abuse |
    • January24

      Just more junk science. No better than reading tea leaves.

      April 2, 2012 at 8:48 pm | Report abuse |
    • dt

      no recordings of martin's voice to compare to – yet. and he is dead.

      April 2, 2012 at 8:58 pm | Report abuse |
  2. babyunk

    I am confused first if trayvon was on top of zimmerman what occured during the fight that zimmerman ended up back on his feet was there a pause when he pulled his gun and trayvon got off of him and stood up if so why did he shoot him he clearly didnt shoot him while trayvon was on top other wise he would have been soaked in blood so if there was a pause when trayvon saw his gun and he got up then zimmerman got up with his gun pointed at trayvon then at that moment he was not being attacked and there was no reason to shoot him im just saying if trayvon was beating this kat up he clearly must have backed off when zimmerman pulled his gun so y shoot this dude is lieing the police lied and from where i see it this case will never see the inside of a court room bcuz if it does alot of lies will b exposed they just are scared to tell the public bcuz they know whats gonna happen

    April 2, 2012 at 8:43 pm | Report abuse |
    • 23 from texas

      Even the though cool Hollywood movies show blood going everywhere (out both entry and exit wounds...) that’s not how it works. Exit wounds bleed more profusely, but often gun wounds do not bleed for several seconds. That leaves plenty of time for GZ to roll dead body off of him and onto the ground, where the police found TM on his back. Also ballistics can prove not only how close someone was when they were shot, but also if they were standing, on their back or on their face pummeling someone. There will be plenty of evidence collected to make a good decision, and I don’t know which side the evidence will prove not guilty, but for anyone to take sides now would be stupid. We just don’t know enough.

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

    There certainly seems to be a lot pointing to charging Zimmerman with SOMETHING. I mean from the audio analysis of the probably racial slur to the cries for help. And WHY wasn't Zimmerman tested for drugs or alcohol? Lets face it no matter what it wasn't a fair fight. ZImmerman was armed and larger.

    April 2, 2012 at 8:45 pm | Report abuse |
    • DDog

      Zimmerman wasn't larger, the pictures the media has been portraying of Martin are from when he was younger.

      April 2, 2012 at 8:48 pm | Report abuse |
    • Rob

      Armed yes, but bigger, not really. They boy was younger, bigger and stronger. Probably more aggressive like in his facebook pics, more violent. But, let law enforcement do their thing and lets see the results. I am sure the family can come up with some audio from the kid that can be compared to the screams.

      April 2, 2012 at 10:50 pm | Report abuse |
  4. Chris

    We all remember when blacks and the left wing publicly convicted and tried to actually convict the innocent white duke lacrosse players, if it weren't for a functioning court system, the left wingers would have allowed those boys to be murdered or imprisoned and then they would have justified it. They are trying to do the exact same thing here and we are not going to allow it. Zimmerman will walk and there aint Sh** you blacks and left wingers can do about it.

    April 2, 2012 at 8:46 pm | Report abuse |
    • steve

      yes he will walk
      and that tramp that ruined those lacrosse players lives will rot in hell with the needles still in her arms! yet they will not be delivering the heroin she craves!
      love it

      April 2, 2012 at 9:11 pm | Report abuse |
  5. NamDebra

    Sry my last post was incomplete... If the kid had been shot in the back it would have made headlines... So if the kid didnt jump on top of zimmerman after punching him, how did he end up shot, face down in the grass? I'm not saying zimmerman didn't 'jumped the gun', so to speak, by using his gun instead of his fists to fight trayvon off... The evidence is there though... Zimmermans back was wet and grassy, trayvon was found face down.. If the kid hadn't jumped/tackled zimmerman after confronting him, which resulted in zimmerman shooting him, how did he end up face down? Seems like there was a physical struggle where trayvon was on top of zimmerman, zimmerman took the easy way out using his gun, instead of his fists...

    April 2, 2012 at 8:52 pm | Report abuse |
  6. antagonist

    Whey are we still debating about a sweet little 12 year old (oh wait he was a 17 year old football player, possibly thug), when a much more heinous crime is still unjustified...the blatant killing of 2 people at the miami funeral. granted any death is a shame, but what's with all the hype in this one?!!

    And quit making it about race... like this is the first black person Zimmerman ever saw and suddenly he wanted to kill him.

    April 2, 2012 at 8:52 pm | Report abuse |
    • Nameless

      You honestly Think this was the first black person he ever saw? You must dumber then you are ignorant.

      April 2, 2012 at 9:21 pm | Report abuse |
  7. Chris

    Zimmerman wasn't 250 lbs, I just saw the the video where he is at the police station, he is a small dude. CNN and the rest of the left wing media has lied about EVERYTHING concerning this incident. They lied about Zimmermans size, they lied about Martins size "he was over 6ft tall when he was shot, not the little child they media has shown." they lied about what led up to the shooting. They just lied about everything. CNN, MSNBC and the other left wing outlets need to be investigated by the FBI for incident race riots over lies. CNN needs to be visited by federal authorities, they cannot be allowed to get away with what they just did.

    April 2, 2012 at 8:57 pm | Report abuse |
    • cherry

      yeah...and they should believe you instead...

      April 2, 2012 at 9:07 pm | Report abuse |
    • steve

      this is all the lies people conjure up in their sick lil minds!
      the guy is free and will never spend a day in jail people know this yet can't accept it
      move on!

      April 2, 2012 at 9:13 pm | Report abuse |
    • JusticeForGeorgeZimmerman

      Chris-You are correct. CNN and the people calling for hate and violence should be investigated. They DID lie about everything in this case. Zimmerman was smaller. Trayvon was taller (over 6ft.) Pictures used by the family and CNN were of Trayvon when he was much younger. George Zimmerman did NOT continue to follow after 911 told they didn't need him to do that. Trayvon came back around and attacked George. EVERYTHING has been distorted and LIED about in order to inflame people. The truth will surface, and it will be known that George was screaming for help and shot when he had no other choice. George was also treated(cleaned up) AT THE SCENE. Racist people want to turn this into something it is NOT. All Trayvon had to do is say he was there visiting–NOT ATTACK george zimmerman. Many of these people want an excuse to be hateful and violent. I hope these racist thugs end up in jail for what they have done.

      April 2, 2012 at 9:26 pm | Report abuse |
  8. Bugman

    Where is the outrage accross America and from mainstream media, including CNN, regarding the numerous murders that occur in black inner city American communities each and every week? Are they any less important than the Sanford, FL shooting? Could it be because the Sanford, FL case is more interesting because this involves hispanic and black persons? The young, black, inner city male population is being dessimated accross America from senseless shootings and no one seems to care. Where is the uproar? Where is Al Sharpton and Jessie Jackson on these killings? No Where!!!

    April 2, 2012 at 8:58 pm | Report abuse |
    • steve

      those don't count in the eyes of that low life thugs jackson and sharpton!

      April 2, 2012 at 9:15 pm | Report abuse |
  9. Bob

    Zimmerman's story(stories) don't add up. If Martin was on top of him, beating him and they Zimmerman shot him, Martin would have 1) Fallen forward on top of him (people don't get blown backwards by pistols except in the movies, they drop in place) 2) He would bled all over Zimmerman. Zimmerman was clean at the scene. The EMTs saw no serious marks on him. If there was any bleeding 1) They would have taken Zimmerman to the hospital 2) The police and EMTs would have been wearing gloves for their own safety. ANY blood = automatic put on gloves. The fact that fifteen minutes after the shooting we have a clean, unruffled Zimmerman on video AND the EMTs didn't report any injuries to Zimmerman to their dispatch say that he had none at the scene. The police report is in no way time-stamped so they could have written in any time after the fact that Zimmerman had injuries to justify letting him go (beside the obvious that the police were a bunch of good-ole-boys who bought the story that Zimmerman felt "threatened") when the outcry started. The timeline (and the statements of the EMTs) doesn't allow for Zimmerman to have been injured, treated, cleaned up, and then transported to the police station to appear in immaculate condition on the video tape in the space of fifteen minutes.

    April 2, 2012 at 8:59 pm | Report abuse |
    • cherry

      zimmerman should have been arrested on that same day,the fact that he killed someone,that is not an excuse..stand their ground...he was the one who followed trayvon,he iniated,provoke indeed,if ever trayvon fight back it is justifiable because he was being hurt,he defended himself clearly...but the police made a mistake and it is clear that they want to cover up everything they could..because from the witnesses,taped from 911 calls,those were enough evidence to prosecute zimmerman...and the man changing his stories because he heard that there were screams in 911,and when he thinks those were not clear,he claimed he was the sreaming

      April 2, 2012 at 9:24 pm | Report abuse |
  10. Avoice

    I wish more people knew about the horrific killing of Kenneth Chamberlain Sr of White Plains NY. RIP from one Vet to another.

    April 2, 2012 at 9:01 pm | Report abuse |
  11. Loyal Northern Democrat

    Ooohhh Long Johnson.... long long Johnson....

    April 2, 2012 at 9:02 pm | Report abuse |
  12. NamDebra

    Ummm..it depends on where trayvon was shot inregards to how much he would have bled immediately after being shot, and I doubt that zimmerman wou

    April 2, 2012 at 9:03 pm | Report abuse |
  13. ketrout

    To me Soledad is attempting to show that it was NOT the voice or screams of Zimmerman. By taking and splicing various sections of the 911 call and then comparing it is very bad science.

    I personally believe that Martin was the aggressor and Zimmerman was the victim. The media needs to allow the legal system do its work and stop making it sound as if Zimmerman is the bad guy.

    April 2, 2012 at 9:08 pm | Report abuse |
  14. Avoice

    Kenneth Chamberlain Sr of White Plains NY. Accidentally pressed his medical alert button while sleeping, the police stormed into his home and shot and killed him. They didn't realize the medical alert company was recording audio of the entire incident. He told them he was ok and please leave him alone. They claimed he had a knife. Their own video shows no knife. WHY is America not talking about this?

    April 2, 2012 at 9:08 pm | Report abuse |
  15. NamDebra

    It depends on where trayvon was shot, the size of entrance wound etc in regards to how much je would have bled in the minutes afterwards that zimmerman wriggled out from underneath him, couple that with the fact that trayvon was dressed in layers(hence the hoodie that has become so famous for all the wrong reasons), so there is a real chance zimmerman could have gotten out from under trayvon before he started to bleed through his clothes... This isnt hollywood or the movies where evry gunshot wound causes gushing spattering wounds

    April 2, 2012 at 9:12 pm | Report abuse |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18