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George Zimmerman Requests Frye Hearing on 911 Call Screams

George Zimmerman's lawyers have filed a motion seeking a Frye hearing to determine the admissibility of the testimony of any voice experts the state may want to call at his trial on the issue of who was screaming in the background of Witness 11's 911 call to police. The motion is here.

The Martin family thinks it was Trayvon screaming. Zimmerman's family is equally insistent it was George. FBI experts stated no conclusion could be reached due to the quality and nature of the recording.

The Orlando Sentinel retained two experts who used different methods. Tom Owen concluded it was not George but having never heard Trayvon's voice, he couldn't conclude it was Trayvon. He used a new biometric program he developed. The other expert used a different technique and concluded a young male was screaming. (He had never heard Trayvon's voice either.)

I discussed the reliability of voice biometrics here. [More...]

Federal courts use Daubert, not Frye, so I won't predict how Judge Nelson would rule. While a Florida appeals court approved voice spectrographic analysis in 1972 (Alea v. State, 265 So. 2d 96 (Fla. Dist. Ct. App. 3d Dist. 1972), it noted the evidence was being used for corroborative purposes, not as the sole means of identification. The last time I checked (several months ago) the Florida courts had not addressed biometric voice analysis.

The Court granted O'Mara's request for subpoenas to the Martin family several months ago for any recordings they had of Trayvon's voice. I have not read any reports as to whether they provided any.

It seems to me the methodology of both Owens and Primeau is inadequate. You can't compare a person's speaking voice to a scream, and the quality of the 911 call was poor. O'Mara has asked the state to provide the "cleaned up copy" Martin family lawyer Ben Crump claimed the state provided Tracy Martin, who Investigator Serino said initially told him it was not Trayvon's voice. It will be interesting to see if the state provided its experts or the FBI with a "cleaned up copy" and when, and if they did, how they explain neglecting to provide it to the defense. If there is such a copy, the defense has a right to have its experts analyze it. It's doubtful that could be done before the present trial date. Maybe George will get his continuance after all.

On the voice issue, also see Legal Insurrection and Tom Maguire.

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    The other expert was Ed Primeau (none / 0) (#1)
    by leftwig on Mon May 06, 2013 at 03:31:42 PM EST
    He said after listening to his enhancement of the audio tape, he concluded it was a young man screaming.  He did not provide any insight as to how old that "young man" might be or what his conclusion was based on.  It seemed to me he ruled out GZ because of his age, not because he compared a clip of GZ's voice to the 911 call.  

    What to glean from a scream (none / 0) (#2)
    by citizenjeff on Mon May 06, 2013 at 04:06:05 PM EST
    Even if it were Trayvon who screamed, what would it indicate? That he was angry and/or fearful? So what? Would it establish that Zimmerman attacked first, or that Zimmerman used more force than necessary? I think not. The only way I think it could help the prosecution is if we hear gunfire during or immediately after the scream, and we're certain that it's Trayvon screaming. That, of course, is not what we hear.

    Where is Your Proof Mr. Owen? (none / 0) (#3)
    by RickyJim on Mon May 06, 2013 at 04:29:47 PM EST
    Reached for comment, Owen told TheDC that he has conducted his own study -- "The Owen Study" -- of more than 400 different pitches, screams, and voice disguises. The study is unpublished.
    Daily Caller article here.

    He has over a year to publish his study to prove his claims but I can't find anything he has published recently.  As the references Jeralyn gave show, he is has much grander pretensions for his program than he ever made for his own abilities to compare voices from different audio sources, made under different conditions.  Frye requires expert testimony be based on established science.  I think it is a distinct possibility that the prosecution's response to the defense's motion will be to say that they don't plan to call any audio experts, similar to what happened with Witness #8's hospital records.

    RE: Frye v. Daubert (none / 0) (#4)
    by scribe on Mon May 06, 2013 at 04:33:57 PM EST
    I think you'll find, TL, that when all is said and done there's not a lot of difference between Frye and Daubert as those cases are applied in the courts.  I think the real difference is in verbiage, not result.

    It is a fact that a teenaged boy's voice ... (none / 0) (#5)
    by Donald from Hawaii on Mon May 06, 2013 at 05:48:33 PM EST
    ... is often a whole octave higher than that of a fully grown man. Having listened earlier to the tape myself, and given what I heard -- emphasis on "given what I heard" -- I would have to conclude that those screams did not belong to then-28-year-old George Zimmerman. Rather, it sounded like a teenaged boy in distress.

    But with that said, I fully agree with Jeralyn that the overall quality of those 9-1-1 recordings was not exactly stellar, which can lead one to rightly wonder whether any subsequent attempts to enhance or "clean up" that quality perhaps also altered or distorted what we're subsequently hearing on these recordings. Also, the speed at which a recorded voice is played back to a listener can markedly alter that voice's pitch and tone, which increases the chance for misidentification.

    (Question, J: were these 9-1-1 recordings originally digital, or were they analog? Anyone who's ever heard the same analog tape played on two different machines -- i.e., one that's older and a tad slower, while the other one is newer and a tad faster -- could testify regarding the discernible differences in quality, pitch and tone.)

    Further, one expert's opinion is still exactly that -- an opinion. Therefore, since we probably cannot fully guarantee that any enhancement of the tape's content didn't also further alter its overall quality for purposes of identification, I believe that this witness's testimony to that effect should be excluded.

    While I believe that the spoken content of the 9-1-1 tape itself -- i.e., what was actually said by both caller and operator -- can be presented to the jury (for whatever that's worth), any discussion regarding its ambient background noises is firmly rooted in opinion. And any opinion that's based upon a nebulous quality, rather than an unambiguous fact, is nothing but further speculation and conjecture.

    We've certainly had enough of that in this case to last us several lifetimes.

    Aloha.

    prepubescent voices (none / 0) (#6)
    by Philly on Mon May 06, 2013 at 07:33:37 PM EST
    ... is often a whole octave higher than that of a fully grown man.

    I don't think your assumption is necessarily accurate.  Voice change in males normally occurs around 12 or 13 years of age.  The larynx typically grows by about 60% causing a pitch drop of a few semitones.  The biggest changes are normally attained by 15 years.

    Parent

    That, and the one sample of Trayvon's voice (none / 0) (#13)
    by Kyreth on Tue May 07, 2013 at 03:11:07 AM EST
    that we do have, as poor and short as it is, is deeper than George's voice (who IMO has a very young, meek sounding voice for his age).

    I have no problem believing that it was George screaming.

    Parent

    Certainly an individual male voice (none / 0) (#7)
    by leftwig on Mon May 06, 2013 at 08:27:32 PM EST
    almost always gets deeper with age, puberty resulting in the most noticeable jump.  The problem with your conclusion is, not every male has the same frequency in their voice.  Many men of 20+ have higher pitched voices than males in their teens.  We have limited sound bites of TMs voice, but it seems to be clearly deeper than GZ's.  How would one go about showing evidence of who had the deeper voice between TM and GZ and then how could one use that knowledge to determine who was screaming in distress (with an altered voice)?

    Parent
    Geddy Lee of Rush (none / 0) (#8)
    by cboldt on Mon May 06, 2013 at 08:54:19 PM EST
    born Gary Lee Weinrib, for what it's worth.  Anyway, yeah, what you said.  Some males have higher pitch voices.  Strangers to Martin and Zimmerman have no way to judge.

    Parent
    7-11 video w/sound (none / 0) (#9)
    by lily on Tue May 07, 2013 at 01:03:24 AM EST
    That's a much better crummy version... (none / 0) (#12)
    by unitron on Tue May 07, 2013 at 01:52:13 AM EST
    ...of the audio than I've heard previously (although there's still too much of the air handling system or the slushy machine), and he doesn't exactly sound like a tenor.

    Of course speaking voice and incoherent screaming in terror voice may vary one from the other in any given individual.

    Parent

    Like father like son (none / 0) (#10)
    by lily on Tue May 07, 2013 at 01:21:48 AM EST
    Tracy Martin has a deep toned voice.
    George Zimmerman and his dad have higher registers.

    Parent
    However, my speaking voice, ... (none / 0) (#11)
    by unitron on Tue May 07, 2013 at 01:46:47 AM EST
    ...which isn't much deeper than it was when I was 17, is probably nearly an octave lower than Zimmerman's and there are plenty of other males with voices even deeper than mine.

    Parent
    Witness' statement and better 7-11 audio (none / 0) (#16)
    by lily on Tue May 07, 2013 at 11:26:31 AM EST
    Thanks (none / 0) (#17)
    by nomatter0nevermind on Tue May 07, 2013 at 01:37:32 PM EST
    That's a really good video.

    Parent
    there's no way a rational person (1.00 / 2) (#18)
    by lily on Tue May 07, 2013 at 01:40:05 PM EST
    could think it was TM yelling for help, he was telling GZ to STFU while GZ desperately hoped someone would come to his aid.

    Parent
    Witnesses (none / 0) (#15)
    by nomatter0nevermind on Tue May 07, 2013 at 08:54:38 AM EST
    It may be worth noting the statements of the witnesses, who heard the calls for help without filtering through phone or recorder. None of them said the voice sounded notably high-pitched or youthful in their earliest statements.  

    Its Apples and Oranges (none / 0) (#19)
    by RickyJim on Tue May 07, 2013 at 05:17:42 PM EST
    You just can't compare a scream and a normal speaking voice.  Has anybody bothered to record themselves screaming versus talking normally and listened to the playbacks?  An even more interesting demonstration can come from a countertenor who professionally sings in a quasi falsetto voice to give modern ears  some sort of idea what the castratos of the eighteenth century sounded like.  Here is Andreas Scholl's normal voice.  And here is his countertenor.  Does anybody hear anything that indicates it is the same person in both cases?  And screaming is even a more drastic voice modification than countertenor.

    If any friend or relative of Martin or Zimmerman is allowed to testify on their identification of the screams, the cross examination should focus of all the incidents they can remember where the subject was screaming like that.  I wonder if they would admit any since puberty.

    A Better Link (none / 0) (#20)
    by RickyJim on Tue May 07, 2013 at 06:44:10 PM EST
    Here you can hear Scholl singing in the background while he is speaking.

    Parent
    Robert Zimmerman Sr. (none / 0) (#21)
    by nomatter0nevermind on Tue May 07, 2013 at 07:49:46 PM EST
    In the second bond hearing, in June of 2012, Robert Zimmerman Sr. was asked whether he had heard George scream like that before. I haven't been able to find a complete video or transcript of the hearing, but as I recall Robert Sr. said that he had, on multiple occasions. He was not pressed for details.

    Parent
    Countertenor? (none / 0) (#22)
    by nomatter0nevermind on Tue May 07, 2013 at 07:52:54 PM EST
    And screaming is even a more drastic voice modification than countertenor.

    This is the first time I have heard of 'countertenor'. I have no idea if your assertion is correct or not.

    Parent

    Which assertion? (none / 0) (#23)
    by RickyJim on Tue May 07, 2013 at 08:11:37 PM EST
    Do you doubt that almost nobody would recognize Scholl singing if they were only familiar with his speaking voice?  Only if Sybrina Fulton or Robert Zimmerman Sr testify they are very familiar with their child's post puberty screaming voice does their identification testimony have any probative value.

    Parent
    The One Quoted (none / 0) (#26)
    by nomatter0nevermind on Tue May 07, 2013 at 08:39:51 PM EST

    You're being ridiculous. I quoted the statement I referred to. Why are you asking if I meant a different one? Is it because you have nothing to support the one I questioned?

    Parent
    Sorry, Didn't See the Quote (none / 0) (#27)
    by RickyJim on Tue May 07, 2013 at 09:11:24 PM EST
    Screaming differs from both normal speech and singing in that a scream is an uncontrolled, emotional attempt to force a large amount of air to vibrate past one's vocal cords with as high an amplitude and frequency as possible.  I have never heard of any science on how screams differ from person to person, let alone how they relate to normal speaking.  I don't even believe that anybody has proved that the higher pitched the normal speaking voice is, the higher pitched the scream.  Any judge who allows testimony from people who claim they can differentiate screams, without any checking that they can, doesn't understand evidence.

    Parent
    The thing about counter tenors is they don't sing (none / 0) (#24)
    by oculus on Tue May 07, 2013 at 08:13:11 PM EST
    very loud.

    Parent
    Oh thank you. I am a Scholl (none / 0) (#25)
    by oculus on Tue May 07, 2013 at 08:15:31 PM EST
    afficianado. Beautiful voice.  

    Parent
    Has anyone claimed (none / 0) (#28)
    by NYShooter on Tue May 07, 2013 at 10:04:40 PM EST
    what the screaming, or yelling, was about? I mean, was it just screaming sounds like you would do when confronted by a monster in a horror movie? Or, were there actual words like, "help, or help me, or somebody, anybody, please help me?"  We know what Zimmerman's version is, but did any of the witnesses who heard the yelling say there were any words?"

    W11 and W6 (none / 0) (#29)
    by Cylinder on Wed May 08, 2013 at 01:15:08 AM EST
    W11 describes the sounds as first screaming or grunting sounds which transitioned to screams of [i]help[/i]. As the altercation moved down the dogwalk, W6's attention was drawn to the screams of [i]help[/i].

    Parent