Continuation Part 2 - Discussion of the Amanda Knox case

[Katody Matrass]

They don't apparently

Yes they do. See the parts translated by komponisto earlier.

They [C & V] may may well be correct on this matter - but given the report is what 140 ? pages long I'm surprised (as a layman) that this quantitative aspect isn't addressed in detail.

It is.

Does this report say that RS' DNA is not on the bra clasp - or does it compare quantitatively his profile with the 'noise' / contamination.

Again, the answer is Yes for the first part, the second part I don't understand what you mean - you need to reword it I'm afraid.

 

[Poppy1016]

Halides1, I just had to take the time to congratulate and thank you for your nearly spot on assessment of this case. I know you have spent countless hours researching this case, and I very much appreciate your efforts

 

[LondonJohn]

PS: platonov's cunningly-posed "yes/no" question is similar to one that might be asked if (when) Knox/Sollecito are acquitted. I fully expect at least one of the pro-guilt idiots to ask the following question (with the same false logic as the "did the report say that Sollecito's DNA was not on the bra clasp" question) if (when) there's an acquittal in Hellmann's court:

"Did the court rule that Knox and Sollecito did not commit the crime? Yes or no?"

To which the scrupulously-accurate answer will almost certainly be "no" - but it won't be relevant. All that will be relevant will be that the court did not rule that they did commit the crime. And, by the same token, all that's important in the DNA report is that it says that Sollecito's DNA cannot be ruled as being present.

 

[LondonJohn]

It is not clear to me whether the extra alleles on the bra clasp did or did not arise through contamination (secondary transfer being another possibility). In order for the allele peaks to qualify as contamination, the DNA giving rise to them wold have to be deposited after the clasp was in the custody of law enforcement. In general it is difficult or impossible to know when DNA was deposited without additional information beyond the peaks in the electropherogram. In this instance the exact date at which the clasp came under the control of law enforcement could be debated, making the question even harder to answer.

Most spectroscopists would use the word "noise" to describe the baseline fuzz one sees between one peak and the next. When peaks are large, it is almost impossible to discern on a printed egram. However, I have sometimes seen people use the word noise when they were referring to small peaks in the egram, such as stutters or possibly alleles that arise from small amounts of contamination. This point has confused previous discussions.

Exactly. And you've also alluded here to the other important point about all this: it's virtually impossible to make a quantitative (or even qualitative) assessment of things like noise ratios or stutter frequency unless one actually sees the source data in their entirety. This is exactly what stymied the defence in the first trial: they could only (at best) resort to generic, unspecific discussions about these issues, with absolutely no way of finding out the true situation.

And the reason why they couldn't argue this crucial issue properly in the first trial was that Stefanoni (and Massei) saw fit to withhold the source data from the defence. I hope (and expect) there to be a specific investigative and disciplinary inquiry on this one matter alone (alongside everything else)

 

[LondonJohn]

Note to the "wise former JREF stalwart":

Carla Vecchiotti (not really too difficult a name to spell properly with a tiny amount of application, is it?) is a female.

 

[platonov]

Dorothy called - she wants those shoes back ! Now

My oh My, why such frantic denial on this issue.


Obviously this will be argued in court and C & V may well carry the day on this point. [or not ? ]

I just asked a simple 2 part Q.

Part 2 of which was to do with quantitative comparison.

Seriously, give those heels a break

 

[LondonJohn]

I just remembered one of the favourite idiot "arguments" about the DNA report (ahead of knowledge of its contents, obviously):

"Hellmann has requested this report so that he can be shown to have left no stone unturned. The report will confirm Stefanoni's findings, and will close off any further avenues of discussion/appeal for Knox and Sollecito".

Oh dear. Yet those idiots who were making this very argument as recently as last week are now desperately scrabbling for some other rationalisation to shore up their over-invested positions. And of course they've totally...erm..... "forgotten" that this was their previous position on the DNA report. Lovely stuff!

 

[Chris_Halkides]

Elsewhere Fiona wrote, “But as you rightly point out the quantity makes a difference: RS dna is not in comparable quantity and I am puzzled that they have just skated over that.” First, the quantity of DNA has only an oblique relationship to the way in which the DNA was deposited, and my understanding is that forensic geneticists shy away from drawing inferences based on the amount of DNA that was deposited. Second, the peaks which Dr. Stefanoni attributed to Raffaele were not substantially taller than the peaks which have not been attributed to anyone. My reading of Dr. Tagliabracci’s testimony as summarized in the Massei report indicated that some of the peaks were actually smaller in height. All of the other peaks were substantially smaller than Meredith’s profile. However, there is an additional subtlety. The unattributed peaks were observed in only a few loci, whereas the peaks attributed to Raffaele were present in most loci. If the quantity of DNA were calculated on the basis of both peak heights and the number of peaks, then the amount of DNA attributed to Raffaele would be larger than that which is unattributed.

Thank you , Poppy1016.

 

[LondonJohn]

My oh My, why such frantic denial on this issue.


Obviously this will be argued in court and C & V may well carry the day on this point. [or not ? ]

I just asked a simple 2 part Q.

Part 2 of which was to do with quantitative comparison.

Seriously, give those heels a break

Err.... who's in denial here....?

 

[Katody Matrass]

quantitative comparison

Of what ?

 

[LondonJohn]

Elsewhere Fiona wrote, “But as you rightly point out the quantity makes a difference: RS dna is not in comparable quantity and I am puzzled that they have just skated over that.” First, the quantity of DNA has only an oblique relationship to the way in which the DNA was deposited, and my understanding is that forensic geneticists shy away from drawing inferences based on the amount of DNA that was deposited. Second, the peaks which Dr. Stefanoni attributed to Raffaele were not substantially taller than the peaks which have not been attributed to anyone. My reading of Dr. Tagliabracci’s testimony as summarized in the Massei report indicated that some of the peaks were actually smaller in height. All of the other peaks were substantially smaller than Meredith’s profile. However, there is an additional subtlety. The unattributed peaks were observed in only a few loci, whereas the peaks attributed to Raffaele were present in most loci. If the quantity of DNA were calculated on the basis of both peak heights and the number of peaks, then the amount of DNA attributed to Raffaele would be larger than that which is unattributed.

Thank you , Poppy1016.

I wouldn't worry: she has practically zero understanding of DNA science (or science in general), so addressing her ignorance is not of much real value*. Curiously, though, despite her clear ignorance, her tendency always seems to be to posit "interpretations" that tend to support a pro-guilt position. That kind of wooly thinking and cognitive bias has no place on a sceptics' forum.

* I don't think she'd be capable of following your argument here, for example.

 

[LondonJohn]

Of what ?

Don't worry also: (s)he doesn't know what (s)he's talking about either

 

[Chris_Halkides]

Pascali and discovery

ANOTHER idiot "argument": how come the defence experts didn't pick up all this stuff in the new report during the first trial? Surely this means that either the defence experts are incredibly bad at their job, or the new report is not as authoritative as it appears.

Well, this one has a quick and simple answer: the defence experts in the first trial were denied the information from which to draw the correct conclusions.. Only the court (i.e. Massei) had the power to compel the prosecution and the police to hand over all the relevant evidence to enable a proper evaluation of this DNA evidence. Unfortunately, Massei was either too weak or too stupid to do so. But Hellmann was not, thankfully.

LondonJohn,

I agree. For the defense not to receive the electronic data files, standard operating procedures, and other information made the first trial unfair all by itself. Raffale's appeal states that Dr. Pascali asked for information of this nature in 2008. I hope that reforms are put into place that prevent such a lack of discovery from taking place in the future.

 

[Katody Matrass]

Don't worry also: (s)he doesn't know what (s)he's talking about either

I hope there's just problem with expressing thoughts clearly - that we can overcome with some guiding questions.

 

[platonov]

Err.... who's in denial here....?

You and Katody Matrass seem to be.

Elsewhere Fiona wrote, “But as you rightly point out the quantity makes a difference: RS dna is not in comparable quantity and I am puzzled that they have just skated over that.” First, the quantity of DNA has only an oblique relationship to the way in which the DNA was deposited, and my understanding is that forensic geneticists shy away from drawing inferences based on the amount of DNA that was deposited. Second, the peaks which Dr. Stefanoni attributed to Raffaele were not substantially taller than the peaks which have not been attributed to anyone. My reading of Dr. Tagliabracci’s testimony as summarized in the Massei report indicated that some of the peaks were actually smaller in height. All of the other peaks were substantially smaller than Meredith’s profile. However, there is an additional subtlety. The unattributed peaks were observed in only a few loci, whereas the peaks attributed to Raffaele were present in most loci. If the quantity of DNA were calculated on the basis of both peak heights and the number of peaks, then the amount of DNA attributed to Raffaele would be larger than that which is unattributed.

Thank you , Poppy1016.

That's all fine & dandy ETA and the latter part refreshingly (and surprisingly) somewhat to the point.

If C & V haven't addressed this issue directly we shall just have to wait.

In the meantime anybody who wishes can knock themselves out

 

[LondonJohn]

I hope there's just problem with expressing thoughts clearly - that we can overcome with some guiding questions.

A noble thought and a noble aim: but ultimately futile, I fear. After all, that would require an open mind and intellectual honesty from all parties involved...

 

[LondonJohn]

You and Katody Matrass seem to be.

What are we in denial about, exactly?

I'm keen to find out!

 

[Chris_Halkides]

a second male DNA profile

LondonJohn,

With respect to my previous comment, many have tried to draw an inference from the quantity of Raffaele's putative profile. On another subject related to the bra clasp thoughtful wrote, "For instance, what on earth can the significance of the presence of unknown male DNA on the bra hooks be?" I have answered this question many times already, but once more won't hurt. If another man's DNA is on the clasp innocently, then how can one conclude that Raffaele's profile is not there innocently? The answer is that one cannot. The other DNA might have arrived via secondary transfer prior to the clasp's coming under ILE's control, or contamination (which itself can involve primary or secondary transfer).

 

[Katody Matrass]

What are we in denial about, exactly?

I'm keen to find out!

Me too

 

[komponisto]

Italians and science

There has been a suggestion that innocence-believers somehow think Italians are incapable of doing science. This is nonsense. Conti and Vecchiotti are clear counterexamples, as is Carlo Torre. And that's just restricting ourselves to people connected to this case. More broadly, I could cite a whole culture running from Galileo, passing through Enrico Fermi, and including my favorite living Italian, the mathematical logician, science popularizer, and religious skeptic Piergiorgio Odifreddi.

The implication that people like Stefanoni, Mignini, and Massei somehow represent the entire Italian nation is among the more insulting of absurdities to come out of the pro-guilt camp, I must say.