Home > Uncategorized > Mixed reviews for audio forensics ‘expert’ Alan Reich.

Mixed reviews for audio forensics ‘expert’ Alan Reich.

I missed the story in The Washington Post back on May 19, in which former University of Washington professor, PhD in Speech Science, Alan Reich analyzed the screams recorded in the first 911 call. Reich used spectographic analysis to parse out previously unrecognizable language amongst the cries. He asserts the screaming voice says, “I’m begging you,” toward the beginning of the call, and that the last word shouted before the gunshot is “Stop.” I had thought it was “Help” but listening to Reich’s ‘enhancements’ on the Post site, and given that the spectograph seems to be a valid method of distinguishing phonemes, I’ll accept his conclusions on both counts, at least for now.

Reich has also identified a second male voice in the background, much quieter than the screams — and sure enough, he’s right about that as well. It’s right there at 7:16:48.

Reich has more to say though, and methinks he skates out on much thinner ice. Says the Post, “Reich is almost certain he hears this [2nd] voice shout ‘What the f—‘” “Almost” is an interesting qualifier. I can make out a “What?” but not the sound after. Reich also ventures an opinion that the screaming voice is Martin and the 2nd voice is Zimmerman, based on comparisons with samples from Zimmerman’s police call. Well, here we’re back to the same problem I discussed in regard to Tom Owen’s “that’s not George screaming” analysis: not enough “controls’ to satisfy the scientific method and establish the validity of the comparison against known positives and negative findings. Reich also claims the tonal balance of the screams suggests a 17-year-old, not-fully-grown larynx, which is a real stretch.

Finally, “What also struck Reich as he played and replayed the recording was what he did not hear: …no obvious sounds of a physical struggle. ‘Acoustical evidence of slapping, punching, shoving, wrestling, falling, throwing objects, was noticeably absent’,” I’m wondering if Reich has been watching too may action films, and is unaware of the whole concept of Foley. Punching, shoving and falling make nice sounds in the movies — all added by the Foley artist or SFX editor — but in real life they’re not only not-so-loud but kind of dull and thuddish. Which means if there had been that sort of mayhem going on during the call  (and I’m not saying there was), then it’s highly unlikely that a cell phone at some distance would have picked up it’s sound.

The Post article then swings to the other side of the scale, as former FBI analyst James Ryan— just on the basis of listening to the raw call and not having examined Reich’s clips or spectrographs — declares the audio quality to be too degraded to make any valid scientific analyses of it’s contents. The Post reporter obviously asked Ryan some questions about Reich’s general methodology, and Ryan makes some persuasive points regarding some of Reich’s more speculative claims. But I think he is being overly careful. He seems to want absolute certainty, and practical knowledge rarely works that way. It generally remains in the realm of the probabalistic. When Reich says the first phrase is “I’m begging you.” The clip sounds like it could be that, but it’s certainly less than crystal clear. But there are sounds on the recording. The odds that they are some random collection of sonic snippets are very low, and given their complexity, the odds that they are human speech are quite high. If they are speech, then are only so many combinations of words or sounds they could be. There are four syllables there. If they’re not “I’m begging you,” then they have to be something else probable that fits both the sonic pattern and what we know of the speech situation. For example, it’s doubtful either party in a struggle would utter “I’m pecking too.”

Reich has clearly identified a second voice where most of us had only heard one, and he has made strong arguments, backed by evidence, regarding the first and last words heard from the person screaming. However less compelling his other claims may be, until his research on these matters is specifically and effectively refuted, I submit they stand as a valuable contribution to unpacking the mysteries held within the physical evidence.

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