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Summary of Results from Oswald's Paraffin Tests


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(Please see the post following this for information on this thread.)

Changes in red.
Questions in blue.

Introduction

There were two types of tests that were performed to detect the presence of gunshot residues (GSR) collected on paraffin casts of Oswald's hands and right cheek. First, a test where a chemical reacts with nitrates. Second, a neutron activation analysis (NAA) that detects the presence of barium and antimony.

Following is a summary of the results of these tests. The summary is followed by conclusions drawn from the results.

Chemical Reaction Tests for Nitrates

Hands:

The results for the nitrate tests of the hands were found to be positive.

However, false positives on nitrate tests are common due to nitrates being present in ordinary household items. Plus the overall accuracy of this test has since come into question.

In addition, it should be noted that there were almost as many nitrate deposits on Oswald's left hand as on his right, firing hand. This indicates that the source of the nitrate deposits was something other than a gun being fired. Given that Oswald was supposed to have fired his pistol five times that day (with each depositing more nitrates), the fact that more nitrates weren't deposited on his firing hand indicates, with near certainty, that Oswald didn't shoot J.D. Tippit.

After the nitrate test on the cheek came back negative, the Warren Commission decided to trash the test. They ultimately declared nitrate tests to be "completely unreliable" -- including for the hands -- and they stated so in their report.

Still, the original positive results were used by authorities to suggest Oswald's guilt in the killing of both Tippit and Kennedy.

Right Cheek:

The result for the nitrate test of the cheek was found to be negative. This was hidden from the public until Mark Lane started talking about it. The Warren Commission and FBI then decided to trash the reliability of the nitrate tests. (The FBI ran nitrate tests on control subjects, and the results showed the tests to be unreliable. QUESTION: Why would they run these tests unless their goal was to show nitrate testing to be unreliable??)

The fact that the right cheek tested negative for nitrates was ultimately documented in the Warren Commission Report.

NAA Tests for Barium and Antimony

Hands:

The results for the NAA tests of the hands were found to be positive. [QUESTION: Did Oswald's right hand test significantly higher for barium and antimony than his left hand? ANSWER: Yes, significantly higher.]

It should be noted, however, that false positives on these tests are possible due to barium and antimony being present in a number of common substances. In addition, there's a chance that these residues came merely from Oswald handling his revolver.

It should also be noted that, given the high probability that the cheek cast was tampered with for the NAA test, it is likely that the hand casts were tampered with as well. (Why tamper with one but not the other?) That the hand casts were also contaminated is supported by the following statement in General Atomic Report GA-6152 to the AEC, page 11: " ....the results were inconclusive....because of earlier contamination of the casts...." Note the plural word "casts."

Regardless, the Warren Commission concluded that the barium and antimony on Oswald's hands may have come merely from his handling of the rifle and the revolver.

Right Cheek:

The result for the NAA test of the cheek was found to be inconclusive, due to there being too much barium on the back side of the cast (the side that never touched Oswald's face), this being indicative of contamination.

The fact that there was more barium on the back side of the cast than on the side that touched Oswald's cheek is inexplicable. It is highly suggestive that tampering took place.

The level of antimony on the cast was never revealed. A low quantity of antimony would have made the result a negative, no matter how much barium was found on the cheek cast, back or front. Fortunately Pat Speer was able to find the Antimony numbers at the Weisberg Archives at Hood Library. The low level of antimony detected indicates a negative result. [QUESTION: Can anybody confirm this statement?]

Warren Commission Conclusions

  • The paraffin tests provide no evidence that Oswald fired his revolver that day.
    The FBI ran tests from which they and the WC concluded that the nitrate test is unreliable. As for the NAA test, the WC concluded that the barium and antimony on Oswald's hands may have come from his handling the rifle and revolver.
     
  • The paraffin tests provide no evidence that Oswald fired his rifle that day.
    The FBI ran control tests from which they and the WC concluded that the nitrate test is unreliable. As for the NAA test of the cheek, the WC found the result to be inconclusive due to contamination of the cast.
     

[Preliminary] Honest Independent Conclusions

The following conclusions are made under the assumption that the nitrate tests were NOT tampered with. (Unlike with the NAA tests, which exhibited evidence of tampering, there is no direct evidence that tampering took place with the nitrate testing.)

  • Assuming Oswald didn't wash up: It is highly unlikely that Oswald fired at J. D. Tippit.
    Otherwise, the tests are inconclusive.
    [i removed these because Oswald did NOT have a chance to wash up.]

    Had Oswald been the person who shot Tippit five times, his right (firing) hand surely would have tested much higher for nitrates than his left hand did. But it tested only slightly higher.

    As for the positive NAA tests on the hands, the casts were likely tampered with to produce positive results, just as the cheek cast was.
  • Assuming Oswald didn't wash up: It is highly unlikely that Oswald fired at Kennedy.
    Otherwise, the tests are inconclusive.

    Because both the nitrate test and the NAA test for antimony on the cheek produced negative results. The NAA test for barium was inconclusive due to contamination of the cast. (The outside of the cast, which didn't touch Oswald's face, had a greater level of barium than the inside, which did touch Oswald's face.)

Evidence Tampering

[i concocted some of the following section out of thin air. Tom, can you rewrite this section using facts in place of my BS? I did try to guess right, so maybe I got lucky and got some of it right. But really, a number of guesses here.]

It has already been noted that tampering of the NAA tests likely occurred, as evidenced by the fact that there was actually more barium found on the side of the cast that hadn't touched Oswald's cheek than on the side that had.

But what of the nitrate testing?

There is indirect evidence that the nitrate testing was tampered with as well. The Dallas Police Department (DPD) waited eleven hours after arresting Oswald to perform the nitrate tests. This went against standard operating procedure at the time. Normally the test would have been performed as soon as possible, as the concentration of nitrates on the skin diminishes over time. In addition, hands and cheeks can become unnecessarily contaminated if the tests are delayed.

Yet the DPD chose to wait ten or eleven hours before performing the tests. Given the facts that 1) the authorities were willing to (later) tamper with the NAA tests; and 2) were willing to hide any results of the tests exonerating Oswald; it is not unreasonable to assume that they would temper with the nitrate tests as well. The ten hour waiting period may have been used to "pepper" Oswald's hands with nitrates by having him hold certain items.

But if the evidence was tampered with, it wasn't done well. Because, as indicated above, the results of the tests show that Oswald was innocent of shooting both Tippit and Kennedy. [This needs updating.]

 

Edited by Sandy Larsen
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The purpose of this thread is to develop a brief summary of Oswald's paraffin test results. Not only the results as reported by the Warren Commission and its witnesses, but also the true results as would be determined by independent experts today. The content of Post #1 will always be the current version of the summary.

I want to invite forum members to critique the list as I have it and to suggest additions and modifications.

Note that I want to keep the list as brief and as easy to understand as possible, while still reflecting the most pertinent and important facts.

I wish to thank Pat Speer and Tom Neal for providing the basic facts for my summary.

Notable Posts

  • Quotes from the Warren Report regarding the paraffin test results:
    See Post 26 on this page.
  • How it came to be that even positive results were downplayed by the Warren Commission:
    See Post 81 on this page.
  • Table of barium and antimony levels detected on Oswald's hands:
    See Post 74 on this page.
  • Tables of barium and antimony levels detected on control subjects hands:
    See Posts 111 thru 113 on this page.

PERSONAL NOTES

Needs to be Explored

  • Incorporate into The Summary what I learned the WC concluded from the paraffin tests. See Post 26, the three items in the summary list at the end. Item #3 is new.
  • Keep in mind Robert's comment that bolt action rifles would leave little in residues. He says don't trust the FBI test showing 7 of 7 correct positives in NAA testing. It was actually the AEC who did these control tests. The AEC handed the results over to the FBI.
  • How about his palms v. the backs of his hands? IIRC he tested Positive for nitrates on the palms of BOTH hands as well as the back. (Was it the same for the NAA tests? It should be...) How did he get so much on his PALMS while holding the pistol?"

    See the the hand diagram at the top of Pat's Chapter 4d.
  • "Although the cheek cast tested Negative on the face side, it tested Positive on the side that did NOT touch his cheek. Could there be a STRONGER indication that someone tampered with this evidence?"

    Is it true that the side of the cast that did not touch Oswald's cheek tested positive on the NAA test?
  • "Rather than argue as to the relative likelihood of any of these individual examples, how about we assign a 75% chance of each of the above examples being TRUE...although I don't believe that ANY of them are better than 50%, and some are MUCH less.

    "A 75% chance that each of the above actually happened means there's a 13% chance that ALL happened. If any ONE of these are false then he couldn't have fired the pistol."


    This isn't really relevant to this thread. But it's an interesting way of looking at the odds of Oswald shooting Tippit in particular, or the odds of many other things occurring in general. Surely we can apply this concept to other assassination things, like the gun purchase for example.

    (Do a search in this post for Tom's words to locate his entire statistical analysis.)

Working Notes

I need to consider what Tom Neal wrote in Posts 255, 257, 260, and 274:

  1. Is there any mention in your research regarding the number of shots fired v. the amount of GSR expected? Surely, after 5 shots, an "inconclusive" result *suggests* that LHO did NOT fire a handgun, more than it suggests that he did.

    He allegedly fired 5 shots, and that is all the nitrates found on his hands? And that's assuming that DPD was honest when they made up their paperwork, and that all of the "dots" are not artifacts from the copying process.

  2. EVERY shot fired would have put more nitrates on his shooting hand. LHO was right-handed, yet there are almost as many nitrate deposits on his left hand as his right.
  3. How about his palms v. the backs of his hands? IIRC he tested Positive for nitrates on the palms of BOTH hands as well as the back. (Was it the same for the NAA tests? It should be...) How did he get so much on his PALMS while holding the pistol?
  4. The NAA tests were performed months after the casts were made.
  5. In post 274 Tom notes that nitrates and other GSR components (both antimony and barium?) are found on ordinary items.

Albert Doyle wrote the following on another forum:

The actual test showed some small spots on the back of the hand and more residue on the palms than was on the back of the hand.

As DiEugenio correctly pointed-out, the way a normal handgun paraffin test works is the palm is gripping the handle and therefore doesn't get any escaping gas residue.

Posts

Post 255:

Pat Speer said:

"Many participants stated that an acceptable cutoff time is 4 to 6 hours after the shooting event,
whereas some felt that up to 8 hours was appropriate. Still others were comfortable accepting lifts
taken more than 12 hours after the shooting."

The expert testified that it was possible, however, for the test to produce a positive finding even
after six or eight hours, but such findings are described as inconclusive.

At approximately 8:55 PM CST on 11-22-63--a bit more than 8 hours after President Kennedy had been slain
End of PS quote

Since when is 25 minutes "a bit more?" That is a significant part of 8 hours. After 8 hours, "Many" and "Some" say no,
and "still others" are comfortable. How many in a "still others?" That is a seriously weak argument.

Is there any mention in your research regarding the number of shots fired v. the amount of GSR expected? Surely, after
5 shots, an "inconclusive" result *suggests* that LHO did NOT fire a handgun, more than it suggests that he did.

From your research, did LHO test stronger on his right hand than his left? How about his palms v. the backs of his hands?

This is important information, especially when you find something "suggestive"in an "inconclusive" result.

Post 257:

Posted 27 April 2016 - 10:28 AM

Pat Speer, on 27 Apr 2016 - 08:28 AM, said:snapback.png

I see where you're going, Tom. You're trying to write off the results for Oswald's hand casts by claiming the paraffin was applied too long after the shooting to be conclusive.

I'm not writing off anything - unlike you, I'm following the test results. Inconclusive means it doesn't prove anything one way or the other. Your experts, who like you, are eager to find LHO guilty, at no time stated that the test results "suggested" anything. This is your suggestion, not theirs, although from your ambiguous writing it is difficult to tell. Perhaps that was your intent.

I see where you went, Pat. You're trying to write off the results for Oswald's hand casts by claiming an "Inconclusive" means that it "suggests" his guilt, when it actually indicates his innocence.

Pat Speer, on 27 Apr 2016 - 08:28 AM, said:snapback.png

But the truth is that the barium and antimony on Oswald's hand casts came from somewhere

Since you state you have the results, why don't you post the amounts of these substances as detected on LHO? You can also include the control data to show how much is present on someone who did not fire a gun. Yes, these substances can be present on someone's hands who has NOT fired a gun...

Additionally, you didn't answer my questions regarding LHO's palms and the back of EACH hand. IIRC he tested Positive for nitrates on the palms of BOTH hands as well as the back. Was it the same for the NAA tests? It should be...

Pat Speer, on 27 Apr 2016 - 08:28 AM, said:snapback.png

Now, that said, the extra barium on the back of the cheek cast suggests tampering.

Yes, it does. And despite this, you have chosen to believe the results of the hand tests, even putting your own spin on an Inconclusive result. Do I detect more than a "suggestion" of BIAS on your part?

Pat Speer, on 27 Apr 2016 - 08:28 AM, said:snapback.png

A wily lawyer could probably spin this into a reasonable doubt about the hand casts as well.

It doesn't take a "wiley" lawyer or ANY "spin" to prove reasonable doubt here. Particularly in this case where evidence tampering has run rampart. CE-399 for example. Doesn't this "suggest" tampering is even more likely regarding the NAA tests??

Post 260:

Posted 28 April 2016 - 09:53 AM

Pat Speer, on 28 Apr 2016 - 01:29 AM, said:snapback.png

As far as the possibility of tampering...the hand casts tested positive for nitrates. It's doubtful anyone would feel the need to tamper with them.

You have GOT to be kidding with this statement. The casts tested positive = it's doubtful they were tampered with?!!! LHO was not identified at the murder scene, the shooting time was altered, and there was no ballistic match to his .38. ANY tampering that was done would be to produce a positive from a negative. IF the tests had been NEGATIVE, which is NOT what they wanted, THAT would indicate there was no tampering. Your statement is a WC type of logic.

DPD WANTED a positive nitrate test. They knew that the longer they waited, the less chance they had of obtaining one. So why did they wait 8 hours to perform the nitrate tests? Did it take that long to contaminate his hands?

In regard to the hand casts: He allegedly fired 5 shots, and that is all the nitrates found on his hands? And that's assuming that DPD was honest when they made up their paperwork, and that all of the "dots" are not artifacts from the copying process.

The above are ALL indicative of tampering. With their reputation, and the fact that they lied about the negative results to the press, are we to think that DPD/FBI would NEVER tamper with evidence?


"Dr. W.F. Mason of Dallas concluded, after tests, that paraffin casts made of Oswalds hands contained traces of nitrate consistent with the residue on the hands of a person who had recently handled *or* fired a firearm." This doesn't "suggest", it STATES that just HANDLING a pistol (which he did) is enough to produce the results achieved. There goes your entire premise that "suggests" he shot Tippit FIVE times. EVERY shot fired would have put more nitrates on his shooting hand. LHO was right-handed, yet there are almost as many nitrate deposits on his left hand as his right. Did he shoot Tippit 3 times with his right hand, and then 2 times with his left hand? And how did he get so much on his PALMS while holding the pistol?

FALSE POSITIVES:
Cunningham admits: The only negative results were on the 20 people who were run as a control and who had never fired a gun, and even for those people they all got positive reactions at least on one hand.

When asked why the FBI continues to perform paraffin tests if they have so many *false positives*, Cunningham confides: Many local law-enforcement agencies do conduct these tests... However, in reporting, we give them qualified results, since we frequently will get some reaction. Numerous reactions or a few reactions will be found on the casts. However, in no way does this indicate that a person has recently fired a weapon.


Could his hands become contaminated in any way, OTHER than firing a hand gun?
Cunningham: "Then we list a few of the oxidizing agents, the common ones, such as in urine and tobacco and cosmetics and a few other things that one may come in contact with. Even Clorox would give you a positive reaction."

But what about the barium and antimony from the NAA tests:
Norman Redlich memo: "barium and antimony are found on a variety of common substances."



To summarize:

LHO tested positive on his hands.

He handled a pistol and THAT ALONE would produce a positive.

Control subjects who have not even handled a gun, frequently test positive.

The FBI firearms expert stated: "...in no way does this indicate that a person has recently fired a weapon."

Additionally, urine, tobacco, cosmetics, and "a few other things" cause a false positive.

Urine: Did he pee during the 8+ hours prior to his arrest? That seems likely, and as already stated he wasn't allowed to wash his hands. Invalid test.

A "few other things:" How about the handling of cardboard boxes? Nitrates are used in the manufacturing process of cardboard and LHO DID handle cardboard boxes.

The NAA testing ONLY proved that he had handled "common substances."


Conclusion:
Neither the Nitrate test, NOR the NAA test even "suggest" that he fired a rifle OR a pistol.

Post 274:

Jim D. I sent you a PM a while ago apologizing for hijacking this thread. So once again I apologize for what will hopefully be the last OT on this thread.

Mr. Speer continues to cite the alleged results of tests performed over the many years since the assassination as evidence that LHO fired a pistol that day. Note that these "experts" in Mr. Speers writings contradict each other regularly.

My first objection is to Mr. Speer's continuing statements that these test results "suggest" that LHO fired a pistol that day, so he is more likely to have murdered JDT than he is to have murdered the president. In reality they suggest that he did NOT fire a pistol.

Most CTs believe that as part of the plan LHO was to be murdered. No mention is made of the "chance" that JDT tried to kill LHO, and IF he fired a pistol that day, it would be for self-defense. ALWAYS an acceptable defense - ESPECIALLY in Texas.

No test is 100% accurate. But despite this fact, Mr. Speer considers any test result less than 100% negative "suggests" LHO fired a handgun. The test result options are Positive, Negative or Inconclusive. Contrary to those who actually performed the tests, Mr. Speer has personally decided that "Inconclusive" results "suggest" that LHO fired a pistol. However, inconclusive actually means the tests don't indicate a decisive result. Thus an answer to the question did he fire a gun is "We don't know."

Although I have mentioned this fact more than once, Mr. Spear will not acknowledge a simple fact. If he actually was correct in saying there's a "chance" that he fired a gun, then obviously there is a "chance" that he didn't. Which "chance" is greater?

To properly evaluate ANY test results, it is important to consider other factors in addition to the actual test numbers. A few examples:

Were the required steps taken to assure that LHO did not come into contact with any contaminants such as the previously mentioned ordinary household items, like Clorox which according to the experts would give a false positive?

Could a man who handles cardboard boxes at his job test positive for nitrates on his hands but not his face? Yes. There are nitrates present in the boxes, and LHO allegedly tested positive for nitrates on his hands, but NOT on his face.

As a control were any other TSBD employees tested for GSR? No. Is that suspicious? Yes. They certainly had enough time to do this. Remember, even according to Mr. Speer's quoted data from experts, CONTACT with "ordinary household items" would cause a Postive result for the Nitrate, OR NAA tests, AND LHO did NOT test positive in the NAA - his result was "inconclusive."

Were there ANY suspicious circumstances involved prior to or after taking these samples? For example did DPD wait until 7 hours or more after LHO was taken into custody before making the Paraffin Casts when they knew that 4 hours was the normal max allowed time, and that the longer they waited the lower the test results?

Were the test samples PROPERLY obtained and PROPERLY stored by QUALIFIED personnel? Was ANY evidence in this case?

The NAA tests were performed months after the casts were made. Mr. Speer says this didn't matter, but he quotes no one who was QUALIFIED to make that statement. Who had custody of these paraffin casts until the tests were completed? Is there a proper chain of evidence? To my knowledge, NO evidence in this case does, so why wouldn't this be suspect?

Was there ANYTHING suspicious about the results? For example, although the cheek cast tested Negative on the face side, it tested Positive on the side that did NOT touch his cheek. Could there be a STRONGER indication that someone tampered with this evidence? Even Mr. Speer agrees that this indicates likely tampering with the cheek casts. Should we view the results of the hand tests as highly suspicious? Enough to disregard Mr. Speer's "chance" that he fired a gun?

All of the above cast a LARGE doubt that these test results mean anything at all.


Are there OTHER factors that we could combine with these tests results, that could aid in determining whether LHO fired a pistol?

Totally off the top of my head:

1. While DPD was searching for him, LHO had to have walked all the way to the murder scene, without being noticed, and arrived in time to kill JDT.

2. LHO's pistol was determined to have a bent firing pin, and thus it was unable to fire. Yet if LHO fired a pistol that day he had to have put 5 slugs into JDT. What is the "chance" of that happening?

3. The bullets were from LHO's gun even though they could not be linked by ballistics, and that the manufacturers of the bullets in evidence are different from those reported when recovered, and initials are not present when they had been marked.

4. All those shots fired, and not one witness ID'd him on the day it happened. They gave descriptions that didn't match LHO at all, and some said the shooter had companions.

5. There was nothing suspicious about the 7 hour wait for the paraffin casts to be made (see above).

6. There was nothing suspicious about the positive results of the NAA tests on the side of the cast that did NOT touch his cheek (see above), so the hand test results were NOT tampered with.

7. Handling the cardboard cartons at the TSBD would NOT create a positive result for nitrates on his hands.

I have undoubtedly overlooked some other examples, but just using the above examples can we quantify the "chance" that LHO hired a pistol that day?

BOOKMARK

Rather than argue as to the relative likelihood of any of these individual examples, how about we assign a 75% chance of each of the above examples being TRUE...although I don't believe that ANY of them are better than 50%, and some are MUCH less.

A 75% chance that each of the above actually happened means there's a 13% chance that ALL happened. If any ONE of these are false then he couldn't have fired the pistol.

About 1 in 10 is a slim chance... but how about using 50% odds for each item? This yields a 0.68% or 1 chance out of about 150. That's not much of a chance, and I consider the actual odds to be MUCH higher than this... I do NOT think he fired a pistol that day.

I don't have the time to try and come up with odds for the above or any others, but if someone else wants to add items or assign percentages, I'm REALLY curious as to what odds you would assign to LHO firing 5 shots with a pistol that wouldn't fire when tested...or to "rigging" GSR tests to skew the results.

Edited by Sandy Larsen
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Sandy,

I think it's VITAL to include the fact that DPD chose to wait 7-8 hours after LHO was apprehended before making the paraffin casts, and this fact should be included in the bullet summary of the test results. This has never been explained. Knowing that the longer they waiter, the lower the nitrate count would be they chose to wait... The ONLY explanation that occurs to me is that they were working to CONTAMINATE his hands and face. This fact alone is enough to create suspicion. Combined with the later fact of the presence of GSR on the WRONG side of the cheek cast, EVIDENCE TAMPERING becomes a virtual certainty. This fact should also be included in the bullet summary of GSR test results. The results were then lied about, which is tantamount to providing false evidence. With this in mind is there any doubt that "they" would have contaminated the actual evidence?

The only test results that were positive were the GSR tests on his hands. If a defense attorney like Mark Lane (who was selected by LHO's mother to represent LHO at the WC hearings, but rejected in favor of another) were allowed to defend LHO, other TSBD employees would have been given this same test. Considering that handling of cardboard boxes leaves nitrate on the hands, but not the face, It is a virtual certainty these "control" tests would have matched LHO. The fact that these tests were not accomplished, is an obvious indication that "they" feared the test results.

Combining the above, we are left with the conclusions:

1. the test results state he did NOT fire a rifle, and therefore did assassinate the President

2. the cheek cast was tampered with, so the hand cast evidence is almost certainly NOT unreliable.

3. the false reporting by DPD of "positive" results for the nitrate tests, and the "salting" of the cheek cast proves that those responsible for investigating the assassination were willing to tamper with the evidence, and had the means to do so.

Edited by Tom Neal
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Thanks for your comments, Tom. They are very valuable to the summary and also to me personally. Because I like to proclaim, "There is no evidence that Oswald shot the rifle." Hopefully I won't have to water that down to, "There is no definitive evidence that Oswald shot the rifle," or something like that. (At the moment I don't think I'll have to water it down. Because, for example, take the case of the positive results of the nitrate tests on the hands. Assume for a moment that there was no monkey business going on. Well, if the same test showed that a number of other employees tested positive because of what they handled, would we say the there is evidence they shot the rifle? No, I don't think so. We would say that only if false positives are rare.)

I don't know if you noticed, but I've temporarily copied four of your posts (above), so I could data mine them... just in case they get deleted from Jim DiEugenio's thread before I could finish that.

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I don't know if you noticed, but I've temporarily copied four of your posts (above), so I could data mine them... just in case they get deleted from Jim DiEugenio's thread before I could finish that.

I did, and it's a good idea!

Tom

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Okay, I have finished writing the first draft of the summary.

I would appreciate any help that will make the summary as fair and correct as possible. At this time I'd most like to find answers to the questions highlighted in RED in the summary. Remember, the summary is in post #1.

Tom, see the post following this in which I reply to your earlier post.

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Sandy,

I think it's VITAL to include the fact that DPD chose to wait 7-8 hours after LHO was apprehended before making the paraffin casts, and this fact should be included in the bullet summary of the test results. This has never been explained. Knowing that the longer they waiter, the lower the nitrate count would be they chose to wait... The ONLY explanation that occurs to me is that they were working to CONTAMINATE his hands and face. This fact alone is enough to create suspicion. Combined with the later fact of the presence of GSR on the WRONG side of the cheek cast, EVIDENCE TAMPERING becomes a virtual certainty. This fact should also be included in the bullet summary of GSR test results. The results were then lied about, which is tantamount to providing false evidence. With this in mind is there any doubt that "they" would have contaminated the actual evidence?

Tom, I didn't put this directly in the summary of test results because it isn't a test result. But I did include it in its own section. Hopefully you will correct it for me.

The only test results that were positive were the nitrate tests on his hands.

Weren't the NAA tests on the hands positive as well? That's what Pat said. And that is what is currently on the summary.

If a defense attorney like Mark Lane (who was selected by LHO's mother to represent LHO at the WC hearings, but rejected in favor of another) were allowed to defend LHO, other TSBD employees would have been given this same trace. Considering that handling of cardboard boxes leaves nitrate on the hands, but not the face, It is a virtual certainty these "control" tests would have matched LHO. The fact that these tests were not accomplished, is an obvious indication that "they" feared the test results.

Combining the above, we are left with the conclusions:

1. the test results state he did NOT fire a rifle, and therefore did [not] assassinate the President

(You forgot the word "not.")

2. the cheek cast was tampered with, so the hand cast evidence is almost certainly unreliable.

3. the false reporting by DPD of "positive" results for the nitrate tests, and the "salting" of the cheek cast proves that those responsible for investigating the assassination were willing to tamper with the evidence, and had the means to do so.

Here is a questions I have for you. You said:

"Although the cheek cast tested Negative on the face side, it tested Positive on the side that did NOT touch his cheek. Could there be a STRONGER indication that someone tampered with this evidence?"

Are you sure that the side of the cast that did not touch Oswald's cheek actually tested positive on the NAA test? (I knew that it had more barium than on the side that touched Oswald's face. But I didn't know that it tested positive.)

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As I pointed out in Jim D's thread, I would not expect a bolt action rifle to produce even a fraction of the escaped gases toward the shooter that a revolver would produce.

As can be seen in the two photos below, there is a tiny gap between the cylinder of a revolver and the barrel of a revolver.

5968d1386892079-colt-single-action-army-

LCR_25_phatchfinal.jpg

This gap is referred to as the "Cylinder-Barrel Gap" or just Cylinder Gap, for short. As the cartridges for a revolver are in the revolving chamber, it is necessary for a fired bullet to cross this gap on its way to the barrel, where it first encounters the rear part of the barrel that is referred to as the "forcing cone".

If this gap were made too small, it would prevent the revolving chamber from being able to turn past the forcing cone, especially after a couple of rounds have been fired and the metal forcing cone has heated up and expanded somewhat.

This cylinder gap is an inherent fault in all revolvers, and explains why revolvers are so loud, as escaping gases are directed laterally and back from this gap. It also helps to explain the lower muzzle velocities of revolvers as, without a tight seal, propellant gases are unable to apply their full force to an exiting bullet.

As you can imagine, with the shooters hand so close to this gap, it is inevitable there will be gunshot residue on his shooting hand.

OTOH, the rifle barrel and chamber are machined from one piece of steel. Propellant gases are only allowed to escape at the muzzle of the rifle, after the bullet exits. Even if the brass cartridge is not a tight fit in a worn chamber, as soon as the gunpowder is ignited, and before the bullet leaves the cartridge, internal cartridge pressures rise dramatically with the burning powder and, before the pressure rises enough to make the bullet begin to move, these pressures are enough to swell the thin walls of the soft brass cartridge outward; effectively "form fitting" the brass cartridge to the chamber and making a seal that will not allow propellant gases to escape rearward.

There is a gas port on the side of the chamber of most bolt action rifles but, this is only here in the event of a ruptured cartridge or primer to give escaping gases somewhere to go beside in the face of the shooter.

Therefore, the only time a shooter's hands should be anywhere near these gases is when he pulls the bolt back to extract a spent cartridge, and lingering gases in the chamber are drawn out by the vacuum the extracting empty cartridge creates.

Edited by Robert Prudhomme
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As I pointed out in Jim D's thread, I would not expect a bolt action rifle to produce even a fraction of the escaped gases toward the shooter that a revolver would produce.

As can be seen in the two photos below, there is a tiny gap between the cylinder of a revolver and the barrel of a revolver.

5968d1386892079-colt-single-action-army-

LCR_25_phatchfinal.jpg

This gap is referred to as the "Cylinder-Barrel Gap" or just Cylinder Gap, for short. As the cartridges for a revolver are in the revolving chamber, it is necessary for a fired bullet to cross this gap on its way to the barrel, where it first encounters the rear part of the barrel that is referred to as the "forcing cone".

If this gap were made too small, it would prevent the revolving chamber from being able to turn past the forcing cone, especially after a couple of rounds have been fired and the metal forcing cone has heated up and expanded somewhat.

This cylinder gap is an inherent fault in all revolvers, and explains why revolvers are so loud, as escaping gases are directed laterally and back from this gap. It also helps to explain the lower muzzle velocities of revolvers as, without a tight seal, propellant gases are unable to apply their full force to an exiting bullet.

As you can imagine, with the shooters hand so close to this gap, it is inevitable there will be gunshot residue on his shooting hand.

OTOH, the rifle barrel and chamber are machined from one piece of steel. Propellant gases are only allowed to escape at the muzzle of the rifle, after the bullet exits. Even if the brass cartridge is not a tight fit in a worn chamber, as soon as the gunpowder is ignited, and before the bullet leaves the cartridges, internal cartridge pressures rise dramatically with the burning powder and, before the pressure rises enough to make the bullet begin to move, these pressures are enough to swell the thin walls of the soft brass cartridge outward; effectively "form fitting" the brass cartridge to the chamber and making a seal that will not allow propellant gases to escape rearward.

There is a gas port on the side of the chamber of most bolt action rifles but, this is only here in the event of a ruptured cartridge or primer to give escaping gases somewhere to go beside in the face of the shooter.

Therefore, the only time a shooter's hands should be anywhere near these gases is when he pulls the bolt back to extract a spent cartridge, and lingering gases in the chamber are drawn out by the vacuum the extracting empty cartridge creates.

Robert,

Thanks for your comments. What you say makes perfect sense.

I need some time to think about the ramifications of this information. If all I knew was what you wrote here, my conclusion would be that no testing (nitrate or NAA) could detect the firing of a rifle. But that appears not to be the case. As I recall, the WC (FBI?) performed NAA tests on individuals who had fired a Carcano, and every one tested positive on their cheek. So apparently the Carcano does leak sufficiently for the sensitive NAA test to detect GSRs.

I'll keep what you wrote here in mind, let others comment on it, and use it when conclusions can be drawn from it..

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Plume of gsr from an M-1 carbine

PlumestudyM1Carbine.png

Apples and oranges, Pat. The M-1 carbine is a semi-automatic rifle. I was referring to bolt action rifles, which is what Oswald allegedly used.

Piston operated semi-automatic rifles, such as the M-1 carbine, have a gas port partway down the inside of the barrel that allows propellant gases to go through this port and force a short piston under the barrel rearward, opening a rotating bolt to eject an empty shell and deliver a fresh cartridge into the chamber.

The plume you see in the photo is spent propellant gas from this piston. The bolt action rifle does not do this.

Edited by Robert Prudhomme
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As I pointed out in Jim D's thread, I would not expect a bolt action rifle to produce even a fraction of the escaped gases toward the shooter that a revolver would produce.

As can be seen in the two photos below, there is a tiny gap between the cylinder of a revolver and the barrel of a revolver.

5968d1386892079-colt-single-action-army-

LCR_25_phatchfinal.jpg

This gap is referred to as the "Cylinder-Barrel Gap" or just Cylinder Gap, for short. As the cartridges for a revolver are in the revolving chamber, it is necessary for a fired bullet to cross this gap on its way to the barrel, where it first encounters the rear part of the barrel that is referred to as the "forcing cone".

If this gap were made too small, it would prevent the revolving chamber from being able to turn past the forcing cone, especially after a couple of rounds have been fired and the metal forcing cone has heated up and expanded somewhat.

This cylinder gap is an inherent fault in all revolvers, and explains why revolvers are so loud, as escaping gases are directed laterally and back from this gap. It also helps to explain the lower muzzle velocities of revolvers as, without a tight seal, propellant gases are unable to apply their full force to an exiting bullet.

As you can imagine, with the shooters hand so close to this gap, it is inevitable there will be gunshot residue on his shooting hand.

OTOH, the rifle barrel and chamber are machined from one piece of steel. Propellant gases are only allowed to escape at the muzzle of the rifle, after the bullet exits. Even if the brass cartridge is not a tight fit in a worn chamber, as soon as the gunpowder is ignited, and before the bullet leaves the cartridges, internal cartridge pressures rise dramatically with the burning powder and, before the pressure rises enough to make the bullet begin to move, these pressures are enough to swell the thin walls of the soft brass cartridge outward; effectively "form fitting" the brass cartridge to the chamber and making a seal that will not allow propellant gases to escape rearward.

There is a gas port on the side of the chamber of most bolt action rifles but, this is only here in the event of a ruptured cartridge or primer to give escaping gases somewhere to go beside in the face of the shooter.

Therefore, the only time a shooter's hands should be anywhere near these gases is when he pulls the bolt back to extract a spent cartridge, and lingering gases in the chamber are drawn out by the vacuum the extracting empty cartridge creates.

Robert,

Thanks for your comments. What you say makes perfect sense.

I need some time to think about the ramifications of this information. If all I knew was what you wrote here, my conclusion would be that no testing (nitrate or NAA) could detect the firing of a rifle. But that appears not to be the case. As I recall, the WC (FBI?) performed NAA tests on individuals who had fired a Carcano, and every one tested positive on their cheek. So apparently the Carcano does leak sufficiently for the sensitive NAA test to detect GSRs.

I'll keep what you wrote here in mind, let others comment on it, and use it when conclusions can be drawn from it..

When you eject a spent casing by pulling the bolt back, immediately after firing a shot, there is always a wisp of smoke that comes out from the open chamber. This is because as you draw the bolt back, the tightly fitting casing seals against the chamber walls, creating a vacuum much like the plunger in a syringe and drawing in air from the muzzle.

I would not believe every test conducted by the FBI.

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NOTE: This post looks long, but most of it need not be read.

I just skimmed over McAdams' take (here) on the paraffin tests to see if I could find legitimate problems with my summary.

He of course cites the WC/FBI tests showing the large number of false negatives produced by the nitrate test. Pat Speer said that the WC/FBI decided to trash the nitrate test upon discovering that Oswald's cheek tested negative for nitrates. So I take the the WC/FBI tests with a grain of salt.

I wanted to see what else McAdams could dig up regarding false negatives. (It is already accepted by everybody that false positives are a problem.

I will copy here every item McAdams could dig up from the literature on nitrate testing. I will highlight the relevant parts. (Check McAdam's page, linked to above, if you want to know the sources of the following texts.)

Item 1:

The ability to determine whether an individual has fired a firearm is of great significance in the investigation of both homicides and suicides. Thus, over the years a number of tests have been developed in an attempt to fill this need. The first such test was the "paraffin test" also known as the "Dermal Nitrate" or "diphenylamine test."1 It was introduced in the United States in 1933 by Teodoro Gonzalez of the Criminal Identification laboratory, Mexico City police headquarters. In this test, the hands were coated with a layer of paraffin. After cooling, the casts were removed and treated with an acid solution of diphenylamine, a reagent used to detect nitrates and nitrites that originate from gunpowder and may be deposited on the skin after firing a weapon. A positive test was indicated by the presence of blue flecks in the paraffin. Although this test may give positive results on the hands of individuals who fired weapons, it also gives positive results on the hands of individuals who had not fired weapons because of the widespread distribution of nitrates and nitrites in our environment. The paraffin test is in fact nonspecific and is of no use scientifically.

Note that there is nothing here about this test producing false negatives. I highlighted that one sentence only because it states that the test is of "no use." The only reason given for the test being of no use is the fact that it can produce false positives, due to the fact that it reacts to nitrates from both GSR and non-GSR sources. In other words, the reaction is "nonspecific."

Item 2:

The dermal nitrate test (paraffin gauntlet test) is a procedure designed to determine whether a suspect has recently discharged a firearm. Melted paraffin is brushed over the "shooting" hand of a suspect until a thin coat is obtained. The glove can be built up in layers by using thin sheets of fabric until it is about 1/8 inch thick. The diphenylamine reagent is prepared by adding 10 cubic centimeters of concentrated sulfuric acid to 2 milliliters of distilled water. To this is added 0.05 grams of diphenylamine. The reagent is dropped on the paraffin mold with a pipette. Dark blue specks appearing on the inner surface of the cast indicate a positive reaction. . . . Theoretically, the diphenylamine reagent is used to test for the presence of nitrates, which are contained in the residue of gunpowder blown back on the hand in discharging the firearm. . . .

Objections: There are several scientific objections to the test as described above in its simplest form. The role of the nitrate on the hand is that of an oxidizing agent. Other strong oxidizing agents can produce the same effect. Hence, launderers, chemists, pharmacists, and other persons handling bleaches or other oxidizing compounds may have materials on their hands which would yield a positive reaction. Thus the test does not necessarily indicate the presence of nitrates, but establishes merely that an oxidizing substance is present on the hand. In brief, the test is non-specific. Another objection is concerned with the fact that there are many non-incriminating sources of nitrates such as fertilizers, explosives, tobacco, urine, and cosmetics. Certain foods also contain nitrates. Finally, some experimenters have found that it is possible to obtain a negative reaction from the hand of a person who has recently fired many rounds of ammunition. . .

Okay, here is one mention of false negatives being observed by "some experimenters." But nothing more specific than that is given. For all we know, this sentence could be referring specifically to the tests performed by the WC/FBI. (And I have a feeling it is. Those tests, after all, surely were well known among forensic professionals. And this book was published after the assassination, in 1980.)

Nevertheless, I'll give McAdams an add out (in tennis terms) for this one. A one-point advantage.

Now, here's a real kicker... McAdams follows the above paragraph -- the one source supporting his argument -- with the following line:

"Thus, there is plenty of evidence that the paraffin test gives false negatives."

Um... I don't think you've shown that or anything like it, professor. A single source does not indicate "plenty."

The good professor makes two more citations after stating that there is plenty of evidence of false negatives. Let's see what he dug up.

Item 3:

They have found the most alarming inconsistencies. For instance, a woman who could not remember ever having had a firearm in her hand in her life gave positive tests for both hands. Further, men who fired guns all day were sometimes able to remove most of the evidence of this firing by an ordinary washing of their hands with the usual soap provided in wash rooms.

I'm not sure that washing GSRs out and then being tested negative for them would be considered a false negative. But nice try, professor. I think we all could have figured out that washing up removes GSRs.

Item 4:

The paraffin glove test for dermal nitrates is neither sufficiently certain nor subject to such scientific accuracy as to justify its routine use in establishing whether a suspect or deceased did or did not fire a gun.

I have to hand it to McAdams, that he was able to come up with a pre-assassination source (1955) indicating that false negatives are possible. He provides a link to the source, so we are able to read it and make our own conclusions.

The authors of this study instructed a technician to perform nitrate tests on the hands of fifteen subjects, six of whom had shot themselves dead, and nine of whom died of other causes (i.e. had not fired a gun). Each of the two authors interpreted the results. Here are the results for the six who had fired a gun:

Author 1

Positive: 3

Inconclusive: 3

Negative: 0

Author 2

Positive: 5

Inconclusive: 0

Negative: 1

Obviously these results make the test look less than conclusive. However, there is a big problem with this study... beside the fact that it had only six subject and doesn't specify the type of gun used.

If you read the paper carefully, you might notice that one of the authors is actually the technician who performed the tests. This is important because the technician had, as noted in the paper, five years of experience performing the test. The other author, a coroner, appears to have no experience performing the test. I think it is reasonable to assume that he had no training, and thus most likely no experience. (How many coroners also perform paraffin tests?)

You may have noticed in the test results I posted above, that one of the authors did quite well in determining which subjects had fired a gun. (Incidentally, this same author also happened to do well in determining those who had not fired a gun.) That author, of course, was the experienced technician. The author who didn't do so well was the inexperienced coroner. No big surprise there.

BTW, the coroner and technician who authored the study were working together at the San Francisco Coroner's Office at the time.

I think one should question why a coroner, of all people, would decide to perform this study, and why he would decide to include himself as an interpreter of the tests considering that he had a trained, experienced technician fully capable of interpreting the tests. I believe that the coroner, as well as the technician, haf a bias against the test. They wrote the following in the paper:

The technician, .... by virtue of his experience, was prepared to say that despite certain cases giving positive tests, he had the "feeling" that the intensity and distribution of the positive reaction was, in his opinion, not due to gunpowder and that the test could be called negative rather than inconclusive.

Okay, so the experienced technician, who got nearly all fifteen cases right (positive and negative), had a feeling that some of the positives he had noted should really have been counted as negatives. If that's true, then why did he count them as positive? Probably because that is what the protocol told him to do. The protocol was right, and the technician wrong.

It's ironic that the technician was so good at performing a test he doesn't trust.

I'm pretty sure that it was the coroner who wrote the following:

In view of the fact that the test reveals only the presence or absence of nitrates and can in no way conclusively differentiate as to the origin or source of the nitrates, it would seem safer to presume that any test showing even small amounts of nitrates should be deemed inconclusive. Any test showing large amounts can only be presumptively positive for having resulted from the firing of a gun.

I believe it was the coroner who wrote it because his interpretations of the test reflect precisely what was written here. That there should be more inconclusives rather than positives.

I believe that what the coroner was attempting to do with this study is ultimately get the test banned, or at the very least have changed the positive/inconclusive threshold so that the test would be more conservative. I can't blame him for that... it is a tragedy that some people are falsely identified as murderers.

Conclusions

What I conclude from the proceeding is that false negatives will occur if the person performing the nitrate test doesn't follow protocol. If the test is performed by a competent person who follows protocol, the number of true negatives will far outnumber the number of false negatives. But false negatives will indeed occur.

A larger study would be more useful.

Edited by Sandy Larsen
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When you eject a spent casing by pulling the bolt back, immediately after firing a shot, there is always a wisp of smoke that comes out from the open chamber. This is because as you draw the bolt back, the tightly fitting casing seals against the chamber walls, creating a vacuum much like the plunger in a syringe and drawing in air from the muzzle.

I would not believe every test conducted by the FBI.

I found this PDF file that has to do with GSR deposits from rifles. (I think the same one Pat got his plume picture from.) It shows the plume from various rifles, including one bolt action rifle, the Winchester 70 (on page 81). The plume for the Winchester is indeed small, though it is as large as one semiautomatic, the Remington 550. Maybe that is explained by its smaller (.22).caliber

Quoting from the article:

The most consistent area of plume concentration for rifles and shotguns

is the crook of the support arm; however, blow-back or drift of the original

plume formation is toward the chest, shoulder, face, and hair, with heavy

concentrations for some weapons and light for others. Again, cartridge ejection

is a factor in many of these weapons. Even when influenced by the

direction of cartridge ejection, the plume expands quickly in all directions

and can also be influenced by turbulent air in the vicinity of discharge.

From what it states here, and from the fact that the Carcano is bolt action, I get the impression that it would be tough to get significant GSR on the cheeks or hands.

On the other hand, maybe the Carcano leaks GSR (if that's possible for a bolt action rifle).

You're right Robert, I shouldn't trust the FBI's control tests. After all, the FBI resorted t trashing the nitrate test when it didn't produce a positive result on the cheek. So it stands to reason they would do the opposite with the NAA tests when they were banking on it.

There is a bit of a problem not trusting the FBI's NAA control tests, though. And that is because (and I just discovered this) the test were actually performed by AEC. (I guess that is the Atomic Energy Commission.) But the results *were* given to the FBI. Who knows what happened after that.

Can anybody shed any more light on this? Pat?

Edited by Sandy Larsen
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