Thursday, 24 July 2014

How Dave Reitzes Gets it Wrong Part 4

Shots in the Dark


The Dallas Police dictabelt recording, previously mentioned in part two of this critique, is the only piece of evidence that has ever changed the way the Kennedy assassination has been reported by officialdom; albeit for all too brief a time. The way Reitzes chooses to cover this particular topic is revealing to say the least. It certainly makes a mockery of Skeptic's claim that it promotes science and critical thinking since these two things are notable only by their absence. For those who are new to the subject, the dictabelt is an audio recording of Dallas police radio transmissions made at the time of the assassination by a police motorcycle officer who's microphone had become stuck in the 'on' position. It was brought to the attention of the House Select Committee on Assassinations in the late 1970s by researchers Mary Ferrell and Gary Mack.


As Reitzes describes it, the HSCA “endorsed the findings of a computer science professor and his assistant, indicating that a shot had indeed been fired from the grassy knoll.” This description of the committee's experts is laughably inept, incomplete, and clearly intended to downplay their expertise. Analysis of the acoustics data was, in actual fact, undertaken by two independent teams of scientists who were at the very top of their profession. To find someone with the requisite qualifications to conduct an analysis of the tape, the HSCA asked the Acoustical Society of America for a short list of leading experts in the field. Top of the list was the Cambridge, Massachusetts, firm of Bolt, Baranek and Newman. As the HSCA reported, BBN “specializes in acoustical analysis and performs such work as locating submarines by analyzing underwater sound impulses. It pioneered the technique of using sound recordings to determine the timing and direction of gunfire in an analysis of a tape that was recorded during the shootings at Kent State University in 1970.” (HSCA report, p. 67)


The second team of experts recommended by the ASA was that of Mark Weiss and Ernest Aschkenasy of Queens College, New York. As well as being involved in various acoustical projects such as the examination of the Watergate tapes, (Ibid, p. 69) Weiss and Aschkenasy wrote computer programs for processing acoustical data for military applications. For example, a submarine navigates by bouncing sounds of its environment and the on-board computer is able to factor in and adjust for important elements like the vessel's speed and the water temperature which varies with latitude. Weiss and Aschkenasy wrote those software programs for the U.S. Navy. (Thomas, p. 594) They were genuine, proven and trusted acoustical experts, something one would not realise from reading Reitzes' facile characterization.


In his typically misinformed manner, Reitzes writes that the dictabelt “contained no audible sounds of gunfire”, which is factually incorrect. It is not that the sounds are inaudible but that they are mixed in with other white noises making them indiscernible to the human ear. BBN chief scientist, Dr. James Barger, and his colleagues discovered six impulses on the tape occurring at approximately 12:30 pm (the time of the assassination) that it was believed could be gunfire. On-site testing was then conducted in Dealey Plaza with microphones being placed along the parade route on Houston and Elm Streets. Test shots were then fired from the Texas School Book Depository and the Grassy Knoll and recorded at each of the microphones. BBN found that five of the suspect impulses on the dictabelt acoustically matched the echo patterns of tests shots fired in the plaza, the fourth in sequence matching a shot fired from the Knoll. (8HSCA101) However, at that point in time, Barger could only attach a statistical probability rating of 50% to the matching of the Knoll shot. (HSCA report, p. 72)


The HSCA then turned to Weiss and Aschkenasy, asking if they could move that 50-50 probability off center, one way or the other. The sonar experts refined BBN's analysis using, as Dr. Weiss testified, “fundamental things in acoustics...basic well-tested, well-established principles” (5HSCA558) and were able to reduce the margin of error from six one-thousandths of a second to one one-thousandths of a second. Thus, after more than two months of calculations, they were able to move the probability of a Grassy Knoll gunshot from 50 to “95 percent or better”. (Ibid, 556) Dr. Barger and his colleagues at BBN then reviewed the work of Weiss and Aschkenasy, making their own independent calculations, and agreed that “the likelihood of there having been a gun shot from the knoll” was “about 95 percent or possibly better”. (Ibid, 674)


It should come as no real surprise that the work of the HSCA's scientists came under attack long before the committee had finished its work. Dr. Barger even had to dispose of criticisms made by private investigator, Anthony Pellicano, during his second appearance before the committee. (5HSCA671-72) Reitzes claims that when the findings of the acoustics experts “were subjected to peer review by a National Academy of Sciences committee...the failings of the HSCA's conspiracy theory were revealed.” But “peer review” does not accurately describe a group with no intentions of approaching the evidence fairly and objectively deliberately setting out to discredit the work of another.


When the Justice Department commissioned the NAS study, it revealed immediately that it had no interest in conducting an open-minded analysis by offering the chairmanship to none other than Luis Alvarez, a vocal defender of the Warren Commission who had staked his professional reputation on there having been no shots from the Knoll. Alvarez, who had publicly dismissed the acoustics evidence before he even looked at it, wisely declined the position and instead recommended his colleague, Nobel Prize-winning physicist, Norman Ramsey. Nonetheless, Alvarez stayed on as the panel's most active member. (Thomas, p. 618) Needless to say, the conclusions of the “Ramsey Panel”, which did not include a single expert on ballistics or acoustics, were preordained. When Dr. Barger met with the panel to explain and defend his work, Alverez let him know that it didn't actually matter what he said, they were going to shoot down the HSCA's findings regardless. (Ibid, 619)


The Ramsey Panel spent two years going over the acoustics data with a fine tooth comb looking for serious flaws but kept coming up empty handed. In the end, the only significant argument in its report was based on a discovery made not by a member of the panel but by a rock drummer from Ohio named Steve Barber. Before discussing what Barber found, it is important to understand that on the day of the assassination, the Dallas police were using two radio channels. Ch-1 was for routine communications and Ch-2 was for the police escort of the Presidential motorcade. If two police units who were tuned to opposite channels came close to one another, and one opened a microphone, it could capture a broadcast from one channel and simulcast it over the other. This phenomenon, known as “cross-talk”, occurred several times during the five and a half minute sequence during which the motorcycle microphone that recorded the alleged shots was stuck open. These simulcasts are a potential means of synchronizing events between both channels.


Steve Barber acquired a copy of the dictabelt recording that came as a promotional plastic insert with a girlie magazine and, after repeated listens, heard something that nobody else had noticeda barley audible instance of cross-talk in which Dallas Sheriff Bill Decker seems to say the words “...hold everything secure...” These words came from a broadcast Decker made about a minute after the assassination on Ch-2. On Ch-1, they appear only one-half second after the impulses identified as a gunshots by the HSCA acoustics experts. The Ramsey Panel seized Barber's discovery with both hands and with it concluded that whatever the impulses on the tape were they could not be the shots that killed Kennedy because they occurred a minute after the assassination. The HSCA's conclusion of a probable conspiracy had supposedly been “debunked”.


However, in 2001, Dr. Donald Thomas reopened the acoustics debate with a paper published in the British forensics journal, Science & Justice. Dr. Thomas debunked the debunkers, pointing out that the Ramsey Panel had overlooked a second instance of cross-talk, the “Bellah broadcast”, and that using that simulcast to synchronize the transmissions placed the impulses “at the exact instant that John F. Kennedy was assassinated”. Several years later, Dr. Thomas noted that none of the five instances of cross-talk on the recordings actually synchronizes with one another, “Hence, the cross-talk evidence does not prove that the putative gunshots are not synchronous with the shooting.” (Hear No Evil, p. 662) In his original paper, Dr. Thomas pointed out numerous errors made by the Ramsey Panel and called special attention to facts which the panel had been very careful to omit from its report. Namely, the “order in the data”.


If the impulses on the dictabelt are not gunshots then any matches to the test patterns are spurious. Therefore, a match would be equally as likely to occur at the first microphone as the last and the five matches could fall in any one of 125 random sequences. But, as Dr. Thomas explains:


...the matching of the five putative shots were to five microphone positions in the correct topographic order...Moreover, not just the order but the spacing was correct. The time lapse between the five matching impulsive sounds was 1.7, 1.1, 4.8, and 0.7 sec on the evidence tape. The first three impulses obtained their highest matches...at three consecutive microphone locations...which were spaced at 6 m increments on Houston Street. The fourth sound matched to a microphone location on Elm Street...24 m removed [from the previous matching microphone]...and, the last matched to a pattern recorded at the very next microphone location...Thus the order spacing revealed by the matching procedure is an accurate fit with the hypothesis that the sounds were gunshots captured on a microphone of a motorcycle travelling north on Houston Street then Westerly on Elm Street at the time of the assassination.”


Furthermore, the distance from the first matching microphone to the last was 143 feet and the time between the first and last suspect impulse on the tape was 8.3 seconds. In order for the motorcycle with the stuck microphone to cover 143 feet in 8.3 seconds it would need to be travelling at approximately 11 mph—the very speed that the Presidential limousine was travelling on Elm Street. (see Warren Report, p. 49) And lastly, the impulses on the dictabelt synchronize perfectly with the images on the Zapruder film. The most obvious reaction to a shot on the film occurs at frame 313 with the explosion of President Kennedy's head. This is preceded by the flipping up and down of Governor Connally's white Stetson hat between frames 225 and 230; the apparent result of a bullet passing through his wrist. When we align the fourth shot on the dictabeltthe Grassy Knoll shotwith frame 313, the third shot falls precisely as expected at frame 225. Therefore, the exact same 4.8 second gap between shots is found on both the audio and visual evidence.


The above described correlations between the dictabelt recording and all other known data are beyond coincidence. In fact, NASA physicist G. Paul Chambers has calculated the odds of the order in the data and the synchronization of film and audio being random together as “only one chance in eleven billion”. (Chambers, Head Shot: The Science Behind the JFK Assassination, p. 142-143) And yet, as noted, the Ramsey Panel mentioned absolutely none of it. The same is true of Reitzes and the authors he most frequently relies upon such as Gerald Posner, John McAdams and Vincent Bugliosi. In Bugliosi's case this is a particularly egregious omission given that his critique of the acoustics evidence takes up some 66 pages of his endnotes section. 66 pages and yet he could not find room for what I summarized above in just a few short paragraphs? Of course he could. But Bugliosi, Reitzes, the Ramsey Panel and their cohorts know full well that if they disclose the order in the data to their readers they will end up convincing them of the validity of the acoustics evidence.


The order in the data leaves us with only two possible conclusions. Either the Dallas police dictabelt genuinely captured the sounds of the shots that killed President Kennedy, or, as Dr. Thomas remarks, “...within moments of President Kennedy being assassinated a burst of static (perhaps cosmic particles from some supernova, or an eruption of the sun, or a thunderclap in the distance) had occurred, and...these static clusters [gave] rise to seperate patterns that just happened to mimic the echo patterns of three gunshots from the Texas School Book Depository, one gunshot from nearby, and one from the grassy knoll, if recorded over a microphone travelling north on Houston Street then west on Elm Street at 11 mph when the air temperature was 65 degrees F.” (Thomas, p. 625)


I believe most reasonable-minded people will agree that the latter is a notion much too ridiculous to take seriously.




4 comments:

  1. Great four part article Mr. Hay.

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  2. Thanks, Robert. There's more to come!

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  3. Wow. The best discussion of the dictabelt evidence that I've ever read. Simple, brief and yet brilliantly persuasive.

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    1. Glad you enjoyed it, Martin. Now spread the word and let people know that they've been misled about the acoustics!

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