Chris_Halkides
Penultimate Amazing
- Joined
- Dec 8, 2009
- Messages
- 12,578
some problems with the bra clasp as evidence
BobTheDonkey,
In comment #8370, you wrote, “interesting. So where did Raffaele's DNA come from? If there was so much handling, and it's the dirt/dust on the ground - then you most certainly have argued that it came from the dust/dirt. If you want to claim the inspectors/officers handling of the clasp is what deposited the DNA, fine. Where did they bring that DNA from? The cigarette butt was removed weeks before during the initial collection, so what other source of Raffaele's DNA was present in the cottage? And again, we're back to his fingerprints/dust on the door.”
You are playing fast-and-loose with certain words. My previous reference (#8065) to dust was the household dust found on the clasp when it was recovered (it looked like a small dust rag, BTW). Dirt is another matter, and so are fingerprints.
One problem with your comments is that you deliberately ignore the possibility of contamination occurring in the lab, where Raffaele’s DNA is in huge quantity, relative to a single evidence sample. PCR amplifies the amount of DNA by roughly one millionfold, and this fact makes the post-PCR DNA a serious risk in contamination, as I have previously said and backed with cites. Many of us have seen the video where the forensic technicians handle the clasp with gloves, not disposable tools, and put it on the ground (tsig, please take note). These are examples of poor collection technique, and they increase the risk of contamination.
Another problem is that you implictly equate the lack of finding Raffale’s DNA on items other than the clasp and cigarette butt, with the lack of Raffaele’s DNA in the apartment, which is false. Recently I implied that without independent examination of the data files, conclusions about what is or is not present are premature. And one of the problems that you have overlooked the longest is the fact that no other items were taken into custody at the same time as the clasp. But perhaps the most serious problem with the bra clasp is that it is just one piece of evidence, as opposed to the bra itself, or Meredith’s body, neither of which had DNA on them. To posit an attack where Raffaele holds Meredith’s arms but leaves no DNA (as I have heard somewhere) is absurd. For this reason, even if the clasp had only Meredith’s and Raffaele’s DNA on it, and even if the clasp had no other DNA on it, I would look upon it quizzically, as a possible outlier. But these other problems are real as well, and they further reduce the evidentiary value of the clasp, as I will now discuss.
In post #8220 you wrote, “Do I think the clasp is credible? Yes. And the reason is that contamination alone cannot explain the concentration of Raffaele's DNA on the clasp, notably that Raffaele's DNA was found in a higher concentration than any of Meredith's roommates - who's DNA we would expect to see signatures of due to shared laundry facilities/living quarters.” You also imply that I believe that contamination is responsible for the DNA profiles on the clasp.
The most important issue here is your claim that concentration is somehow related to the mechanism of DNA being deposited on the clasp. I have repeatedly asked you and Fulcanelli (#8221) to cite the forensic literature, and you have repeatedly failed to do so. I have repeated offered you evidence to the contrary—citing a profile in the Leskie case that was much stronger than Raffaele’s that came from contamination. Fulcanelli, especially, calls Raffaele’s DNA abundant or copious, in reckless disregard of the fact that it is only 200 RFU in intensity, far weaker than typical profiles. Second, you imply that two of the unknown profiles came from the flatmates, without one scintilla of evidence. Nor do you offer any citations from the literature showing how sharing laundry facilities leads to multiple individuals depositing their DNA. Finally, I have said before that both contamination and secondary transfer are possible routes of transfer. Again, please note that these two possibilities are not the same thing, and lector’s definition of contamination is not quite accurate.
Some unknown person moved the clasp. Therefore, the clasp was not in a secure location by definition. There is no reason to rule out this person as an agent of secondary DNA transfer. Another problem with your analysis is that you don’t differentiate between secondary transfer and contamination. I have said that both are possible.
Next, let me deal with lector’s claim (#8223) that finding the identity of the other three individuals is not the prosecution’s job, because this claim is relevant to your arguments as well. To be concerned with how Raffaele’s DNA got there and not how the other people’s DNA got there is a mistake, and not taking appropriate reference samples was bad forensic science. If RS was a suspect, then so should the other three unknown depositors have been, unless they could be ruled out. Because DNA cannot be interrogated as to how it arrived, if their DNA was deposited innocently on the clasp, there is no reason to assume that RS’s DNA also arrived innocently. Again, Fulcanelli’s arguments about how much is present being indicative of how it came to be deposited are unsupported by literature and contradicted by experts such as Jason Gilder whom I asked.
You wrote (#8259), “Regardless of whether the cottage was sealed, regardless of when the clasp was collected - there was no means for Raffaele's DNA to contaminate the clasp. To claim this is the case is to defy the laws of physics - and yes, I know what I'm claiming.” Later in the same comment, you wrote, “And yet, Raffaele's DNA was found in a concentration of magnitudes greater than that of Amanda (and presumably the other 2 roommates - regardless of whether the two unknowns are the roommates are not, we can be sure that Raffaele's DNA was in a concentration higher than any of Meredith's 3 roommates). So, if anyone would like to continue believing the contamination bit, I'd like to see a valid, rational response as to where, exactly, the DNA came from if not Raffaele himself.” Elsewhere in the same comment you wrote, “We've established that dust is not sufficient to provide such a large concentration of a single individual's DNA.”
That the hypothesis of contamination defies the laws of physics may be the most breathtaking claim I have heard on this thread, and that is quite an accomplishment, considering the competition. And true to form, it is offered without a single citation of the forensic literature. Yet your comment is false on several fronts, some of which I have already delineated. There are three contributors to the clasp, but no complete profiles, so claiming Amanda’s DNA is present is a serious misstatement. There is no reason whatsoever to claim that the other two flatmates deposited their DNA only the clasp without their reference profiles. I have pointed out that the source of DNA contamination is rarely known, and no one here has offered citations to counter to the ones I gave. To put it differently, if one had to prove where contamination originated, one would almost always be unsuccessful, despite the fact that it is known to happen in even the best labs. Yet another problem with your argument is that you claim orders of magnitude difference between Raffaele’s profile and the other three individuals. This is not possible; if the other profiles were even two orders of magnitude lower than his, they would be equal to or less than the level of noise in the electropherograms and would not be observable. Finally, if you look at the electropherogram I showed on the dust thread, you will see that there are peaks with intensities of roughly 2000 RFUs, or about tenfold higher than Raffaele’s profile on the clasp. The authors did not attempt to deconvolute the electropherogram (it was not their area of expertise, nor the point of this particular study); therefore, your claim about what a single individual would provide is an unjustified extrapolation from the data.
Let’s see what those who are among those writing the forensic literature said about the clasp. The Johnson/Hampikian open letter said:
“Raffaele Sollecito had been at the house shared by Amanda and Meredith several times. Furthermore, Amanda, Meredith and their guests shared a bathroom. Transfer of Raffaele’s DNA to the clasp could have occurred through several innocent means as a result of his DNA being in the apartment or via Amanda’s clothing or belongings.
• DNA testing cannot determine how biological material was deposited onto an item of evidence: whether by direct deposit, or by secondary transfer through an intermediary. DNA testing cannot determine how long biological material may have been on an item, or whether contamination occurred during collection.
Conclusions about the bra clasp:
Handling and movement of this sample has compromised its probative value. The laboratory results for this sample cannot reliably be interpreted to show that the DNA of Raffaele Sollecito was actually on the bra clasp at the time of Meredith Kercher’s murder, and it does not establish how or when this DNA was deposited or transferred.”
What I find most troubling is that these problems with your arguments have almost all been pointed out to you before, sometimes repeatedly. Ignorance is one thing (we are all ignorant of many things), but fecklessness is more serious. And at some point your fecklessness on these matters threatens to become something even worse.
halides1
BobTheDonkey,
In comment #8370, you wrote, “interesting. So where did Raffaele's DNA come from? If there was so much handling, and it's the dirt/dust on the ground - then you most certainly have argued that it came from the dust/dirt. If you want to claim the inspectors/officers handling of the clasp is what deposited the DNA, fine. Where did they bring that DNA from? The cigarette butt was removed weeks before during the initial collection, so what other source of Raffaele's DNA was present in the cottage? And again, we're back to his fingerprints/dust on the door.”
You are playing fast-and-loose with certain words. My previous reference (#8065) to dust was the household dust found on the clasp when it was recovered (it looked like a small dust rag, BTW). Dirt is another matter, and so are fingerprints.
One problem with your comments is that you deliberately ignore the possibility of contamination occurring in the lab, where Raffaele’s DNA is in huge quantity, relative to a single evidence sample. PCR amplifies the amount of DNA by roughly one millionfold, and this fact makes the post-PCR DNA a serious risk in contamination, as I have previously said and backed with cites. Many of us have seen the video where the forensic technicians handle the clasp with gloves, not disposable tools, and put it on the ground (tsig, please take note). These are examples of poor collection technique, and they increase the risk of contamination.
Another problem is that you implictly equate the lack of finding Raffale’s DNA on items other than the clasp and cigarette butt, with the lack of Raffaele’s DNA in the apartment, which is false. Recently I implied that without independent examination of the data files, conclusions about what is or is not present are premature. And one of the problems that you have overlooked the longest is the fact that no other items were taken into custody at the same time as the clasp. But perhaps the most serious problem with the bra clasp is that it is just one piece of evidence, as opposed to the bra itself, or Meredith’s body, neither of which had DNA on them. To posit an attack where Raffaele holds Meredith’s arms but leaves no DNA (as I have heard somewhere) is absurd. For this reason, even if the clasp had only Meredith’s and Raffaele’s DNA on it, and even if the clasp had no other DNA on it, I would look upon it quizzically, as a possible outlier. But these other problems are real as well, and they further reduce the evidentiary value of the clasp, as I will now discuss.
In post #8220 you wrote, “Do I think the clasp is credible? Yes. And the reason is that contamination alone cannot explain the concentration of Raffaele's DNA on the clasp, notably that Raffaele's DNA was found in a higher concentration than any of Meredith's roommates - who's DNA we would expect to see signatures of due to shared laundry facilities/living quarters.” You also imply that I believe that contamination is responsible for the DNA profiles on the clasp.
The most important issue here is your claim that concentration is somehow related to the mechanism of DNA being deposited on the clasp. I have repeatedly asked you and Fulcanelli (#8221) to cite the forensic literature, and you have repeatedly failed to do so. I have repeated offered you evidence to the contrary—citing a profile in the Leskie case that was much stronger than Raffaele’s that came from contamination. Fulcanelli, especially, calls Raffaele’s DNA abundant or copious, in reckless disregard of the fact that it is only 200 RFU in intensity, far weaker than typical profiles. Second, you imply that two of the unknown profiles came from the flatmates, without one scintilla of evidence. Nor do you offer any citations from the literature showing how sharing laundry facilities leads to multiple individuals depositing their DNA. Finally, I have said before that both contamination and secondary transfer are possible routes of transfer. Again, please note that these two possibilities are not the same thing, and lector’s definition of contamination is not quite accurate.
Some unknown person moved the clasp. Therefore, the clasp was not in a secure location by definition. There is no reason to rule out this person as an agent of secondary DNA transfer. Another problem with your analysis is that you don’t differentiate between secondary transfer and contamination. I have said that both are possible.
Next, let me deal with lector’s claim (#8223) that finding the identity of the other three individuals is not the prosecution’s job, because this claim is relevant to your arguments as well. To be concerned with how Raffaele’s DNA got there and not how the other people’s DNA got there is a mistake, and not taking appropriate reference samples was bad forensic science. If RS was a suspect, then so should the other three unknown depositors have been, unless they could be ruled out. Because DNA cannot be interrogated as to how it arrived, if their DNA was deposited innocently on the clasp, there is no reason to assume that RS’s DNA also arrived innocently. Again, Fulcanelli’s arguments about how much is present being indicative of how it came to be deposited are unsupported by literature and contradicted by experts such as Jason Gilder whom I asked.
You wrote (#8259), “Regardless of whether the cottage was sealed, regardless of when the clasp was collected - there was no means for Raffaele's DNA to contaminate the clasp. To claim this is the case is to defy the laws of physics - and yes, I know what I'm claiming.” Later in the same comment, you wrote, “And yet, Raffaele's DNA was found in a concentration of magnitudes greater than that of Amanda (and presumably the other 2 roommates - regardless of whether the two unknowns are the roommates are not, we can be sure that Raffaele's DNA was in a concentration higher than any of Meredith's 3 roommates). So, if anyone would like to continue believing the contamination bit, I'd like to see a valid, rational response as to where, exactly, the DNA came from if not Raffaele himself.” Elsewhere in the same comment you wrote, “We've established that dust is not sufficient to provide such a large concentration of a single individual's DNA.”
That the hypothesis of contamination defies the laws of physics may be the most breathtaking claim I have heard on this thread, and that is quite an accomplishment, considering the competition. And true to form, it is offered without a single citation of the forensic literature. Yet your comment is false on several fronts, some of which I have already delineated. There are three contributors to the clasp, but no complete profiles, so claiming Amanda’s DNA is present is a serious misstatement. There is no reason whatsoever to claim that the other two flatmates deposited their DNA only the clasp without their reference profiles. I have pointed out that the source of DNA contamination is rarely known, and no one here has offered citations to counter to the ones I gave. To put it differently, if one had to prove where contamination originated, one would almost always be unsuccessful, despite the fact that it is known to happen in even the best labs. Yet another problem with your argument is that you claim orders of magnitude difference between Raffaele’s profile and the other three individuals. This is not possible; if the other profiles were even two orders of magnitude lower than his, they would be equal to or less than the level of noise in the electropherograms and would not be observable. Finally, if you look at the electropherogram I showed on the dust thread, you will see that there are peaks with intensities of roughly 2000 RFUs, or about tenfold higher than Raffaele’s profile on the clasp. The authors did not attempt to deconvolute the electropherogram (it was not their area of expertise, nor the point of this particular study); therefore, your claim about what a single individual would provide is an unjustified extrapolation from the data.
Let’s see what those who are among those writing the forensic literature said about the clasp. The Johnson/Hampikian open letter said:
“Raffaele Sollecito had been at the house shared by Amanda and Meredith several times. Furthermore, Amanda, Meredith and their guests shared a bathroom. Transfer of Raffaele’s DNA to the clasp could have occurred through several innocent means as a result of his DNA being in the apartment or via Amanda’s clothing or belongings.
• DNA testing cannot determine how biological material was deposited onto an item of evidence: whether by direct deposit, or by secondary transfer through an intermediary. DNA testing cannot determine how long biological material may have been on an item, or whether contamination occurred during collection.
Conclusions about the bra clasp:
Handling and movement of this sample has compromised its probative value. The laboratory results for this sample cannot reliably be interpreted to show that the DNA of Raffaele Sollecito was actually on the bra clasp at the time of Meredith Kercher’s murder, and it does not establish how or when this DNA was deposited or transferred.”
What I find most troubling is that these problems with your arguments have almost all been pointed out to you before, sometimes repeatedly. Ignorance is one thing (we are all ignorant of many things), but fecklessness is more serious. And at some point your fecklessness on these matters threatens to become something even worse.
halides1
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