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Continuation Part Six: Discussion of the Amanda Knox/Raffaele Sollecito case

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You don't know what "sensitivity" means in this context. You're wrong.

I know how it is used in the forensic literature.

Oh really? Does it? Cite please...... (I'll give you a hint: you won't be able to produce a cite, because you're wrong).

Let's try one, then:

http://projects.nfstc.org/workshops - Evaluations of premuptive tests

Tobe, Watson, Nic Dae - Evaluation of Six Presumptive Tests for Blood,
Their Specificity, Sensitivity, and Effect on High Molecular-Weight DNA
- Journal of Forensic Science, January 2007

Tobe said:
“ (..) Based on this, the best overall presumptive blood test in this study was luminol. It had the greatest sensitivity and specificity. It did not destroy the DNA, and it could be reapplied. Its only drawback is that it must be used in near or complete darkness. Leuchomalachite green was found to be as specific to blood as luminol, but its sensitivity was 10 times less, and it destroyed the DNA. Phenolphthalein had equal sensitivity to most of the other tests, but was extremely unspecific, and the amount of recoverable DNA is reduced when this test is used. HemastixTM [TMB] were easy to transport and use, were sensitive, but not very specific although specificity could be increased if the strips were looked at rather than the reaction on the stain.”
 
This simply isn't true. False positives in fact ARE COMMON.
There are countless substances that react to Luminol. Luminol reacts to any substance that contains copper, iron, cyanides, bleaches as well as specific proteins.

Webb, Creamer & Quickenden found something like 9 substances from household environment, none of them common, and most of them volatile or distinguishable from blood.
Metal salts compound are toxic, as well as bleaches, you may find them in gardening or in varnishings but you won't find them in a household environment, and anyway they are not used in contact with the human body.
 
There are no "Satanic conferences", and there is nothing to say beyond what Mignini and the other guests said, which apparently you didn't listen to.

"Delitti & Misteri" is a mainstream magazine about crime and justice, not about Satanism. The guests even basically agreed that Satanism doesn't exist (they said that there was actually no satanic sect not even in the "Bestie di Satana" murders case).
The conference and speakers had a rationalist approach under all points of views.

And the transcript of Mignini's words were.......?
 
Webb, Creamer & Quickenden found something like 9 substances from household environment, none of them common, and most of them volatile or distinguishable from blood.
Metal salts compound are toxic, as well as bleaches, you may find them in gardening or in varnishings but you won't find them in a household environment, and anyway they are not used in contact with the human body.

Fecal matter, soils, bleaches, hydrogen peroxide, horseradish, soil with an iron content, rust just to name a few. And they are NOT distinguishable from blood.
They all just glow.

You need to provide actual cites, not general cites.

But you never answered any of my questions. NOT ONE.

So here it goes again.

  1. Why do forensics manuals instruct techs to perform BOTH TESTS?
  2. Why do forensic manuals instruct techs to perform a confirmatory test?
  3. Why did Stefanoni perform a TMB test if she plans to ignore a negative result?
  4. Why can't you see these prints with the naked eye?
  5. If they were cleaned by Amanda and Raffaele after the crime, why aren't they "streaked"?
 
Fecal matter, soils, bleaches, hydrogen peroxide, horseradish, soil with an iron content, rust just to name a few. And they are NOT distinguishable from blood.
They all just glow.

You need to provide actual cites, not general cites.

But you never answered any of my questions. NOT ONE.

So here it goes again.

  1. Why do forensics manuals instruct techs to perform BOTH TESTS?
  2. Why do forensic manuals instruct techs to perform a confirmatory test?
  3. Why did Stefanoni perform a TMB test if she plans to ignore a negative result?
  4. Why can't you see these prints with the naked eye?
  5. If they were cleaned by Amanda and Raffaele after the crime, why aren't they "streaked"?

Tesla - calm down.

Did you read the PDF Mach linked to?

Do you have the links to the forensic manuals? I would guess that following with TMB adds to indications that it is in fact blood. It seems clear that a very diluted blood trace would test positive (show the glow) with luminol and test negative with TMB.

Although I've tried to get Chris to comment more on the possibility that those bare footprints were left at some time well before the murder from some very diluted bloody water. This from someone with a little blood in the bidet or shower.

My biggest problem with the footprints is that they don't match but are the famous "compatible" and that they don't form a pattern that can be explained without the magical cleanup.

Why Mach, if they cleaned the missing prints so well and without a trace, didn't they use the same technique to clean all the floors?
 
Tesla - calm down.

Did you read the PDF Mach linked to?

Do you have the links to the forensic manuals? I would guess that following with TMB adds to indications that it is in fact blood. It seems clear that a very diluted blood trace would test positive (show the glow) with luminol and test negative with TMB.

Although I've tried to get Chris to comment more on the possibility that those bare footprints were left at some time well before the murder from some very diluted bloody water. This from someone with a little blood in the bidet or shower.

My biggest problem with the footprints is that they don't match but are the famous "compatible" and that they don't form a pattern that can be explained without the magical cleanup.

Why Mach, if they cleaned the missing prints so well and without a trace, didn't they use the same technique to clean all the floors?

The thing that makes me mad about this is it is so deceitful. While it is possible that there can be a false negative TMB test it just isn't likely.

And getting away from the literature there is logic, which escapes the prosecution.

While you can see the luminol prints, you can't see them with the naked eye. But why can we see Rudy's prints with a naked eye? If Amanda and Raffaele had spent the evening cleaning, how did they eliminate all their own visible prints and leave Rudy's visible prints? Did they levitate? If the blood was fresh and it would have been, the Luminol prints would have streaked, but they weren't streaked. So that means these prints were made at different time than the murder.

You can't ignore the fact that Stefanoni went through the standard process of performing both tests, so she KNOWS THE PROTOCOL.

Knock your socks off Grinder.

*Lerner, K. Lee, and Brenda Wilmoth Lerner, eds. (2006). The World of Forensic Science. New York: Gale Group.
Newton, Michael. (2008). The Encyclopedia of Crime Scene Investigation. New York: Info Base Publishing,
Siegel, Jay. (2006). Forensic Science: The Basics. Boca Raton, FL: CRC Press,
Websites
www.biologymad.com/cells/microscopy.htm
www.cengage.com/school/forensicscienceadv
www.fbi.gov/hq/cjisd/takingfps.html
www.forensic-medicine.info/fingerprints.html
http://inventors.about.com/od/mstartinventions/a/microscope.htm
www.microscope-microscope.org/basic/microscope-history.htm
www.nfstc.org/pdi/Subject02/pdi_s02_m02_01_a.htm
www.redwop.com/download/dfo.pdf
www.rpi.edu/dept/chem-eng/Biotech-Environ/CHROMO/chromtypes.html
 
And that's why any competent and semi-knowledgeable forensic scientist then conducts a TMB test on the sample.

Competent and semi-knowledgeable doesn't describe the forensic team in this case.

From the computer "retarded experts", to the interrogation, to the forensic team that can't even count the circles of a tennis shoe...etc..etc..

The scene and evidence was compromised repeatedly by this team and therefore theres nothing to be conclusive in anything they presented. Even if others participated in this crime the forensic team and the other goofballs didn't even come close. We don't even need to mention the mentality of someone like Edgardo Giobbi hanging pictures on his wall before the trials are over, and making his infamous idiotic video of his self proclaimed abilitys to find guilty partys without science, just gut-instinct.
And this is the guy whom the Perugia pack looked to for direction!
 
Grinder,

Take a look at this document about the use of Luminol. In particular look at the pictures at the end of the article where cleanups took place. Then compare that to the images in the Kercher murder.

Now after looking at them both Grinder. Was there a cleanup?
 
WTF - What's the fact?

It isn't that tough to figure this out. Starting with a google search for [TMB blood test], the first hit is:

http://www.nfstc.org/pdi/lab_manual/Linked Documents/Protocols/pdi_lab_pro_2.19.pdf

And the first paragraph begins:

INTRODUCTION
The tetramethylbenzidine (TMB) presumptive test for blood is a catalytic test which is based on the peroxidase-like activity of hemoglobin.​

That word "catalytic" is the key. That means the hemoglobin is not consumed by the reaction so the reaction continues although at a slower rate for even the lowest concentrations. Theoretically the test could return a positive indication with only a single red blood cell present.

Can we say "case closed"?
 
Tesla - calm down.

Did you read the PDF Mach linked to?

Do you have the links to the forensic manuals? I would guess that following with TMB adds to indications that it is in fact blood. It seems clear that a very diluted blood trace would test positive (show the glow) with luminol and test negative with TMB.

Although I've tried to get Chris to comment more on the possibility that those bare footprints were left at some time well before the murder from some very diluted bloody water. This from someone with a little blood in the bidet or shower.

My biggest problem with the footprints is that they don't match but are the famous "compatible" and that they don't form a pattern that can be explained without the magical cleanup.

Why Mach, if they cleaned the missing prints so well and without a trace, didn't they use the same technique to clean all the floors?


They got more luminol reactions at Raffaele's than at the crime scene. They get a lot of false positives with luminol.
 
Hey Charlie Wilkes,
As you are close to the Defence,
do you know if ANY of the samples collected and that show DNA from Rudy Guede
also have the DNA of 4 others too, as that bra clasp that supposedly has Raffaele Sollecito's DNA on it did?
 
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Tell me instead, first when you think the the prosecution was “caught”. Because I could recall several moments, but the choice it depends on what moment you ‘chose’ to say that the defence ‘caught’ someone. Chose an event, which you call the ‘defense catching’ someone, and I’ll demonstrate that – whatever event and moment you chose – there was a previous moment when the prosecution revealed the key information first.
In July 2009, for example, Manuela Comodi stated in court that the total amount of DNA on the metal bra clasp was 1.4 nanograms.
Only at that point, the defence complained that they didn’t have that information.
Comodi replied the information was in the SALs and in the quantization data.
Bongiorno requested the data and complained that she didn’t have them. Comodi pointed out that it was her fault if she didn’t have them, and said the prsecution did not object that they have it now (but they should have thought about it before).
So the judge ordered laboratory to give the ‘documentation’. The laboratory turned out the SALs.
Just like this, all the times information release starts from the prosecution. It is never the defence who ‘catches’ anyone.





Absolutely not. The negative TMB results were just noted in the documentation that the prosecution kindly presented to the defence, despite the defence experts had not attended the meetings they were summoned to with the laboratory staff, and despite the defence did not access the laboratory over the nine months investigation despite defence experts were offered free access to the documentation at Rome laboratory, and they never came.
And, most important, that information was not contending that the luminol prints were made in blood, from the point of view of the prosecution and their experts. It might have been ‘contending’ that only from the point of view of the defence.
It is not an ‘objective’ and ‘manifest’ contention, despite you think it is, for the reasons I already explained.





As I have already said, all information they used to argue about the TMB was extrapolated by documentation which had been previously released by the prosecution
But now you are entangling yourself in your contradictions. If you assert they offered ‘manufactured SALs’, then you should have a shred of evidence of that which you obviously don’t have, and you know that. But now if you instead claim that the defence got the information through the video, then you’re definitely entangled: the defence had been having all those videos for years! The defence experts were even supposed to be present when these videos were shot (they could have actually intervened and could have requested “pleas we want a TMB test on that stain”).
So you are now admitting the prosecution offered all the needed information years before.



Again, the same contradiction. The Stefanoni’s report contains the templates of all tests doen on samples and items. Now, it happens that not always these templates and pages are correct. There is almost always a TMB test indication, either positive or negative. This indication is missing in the luminol sample templates. If it was so easy to expect this test to be done, why didn’t the defence experts immediately notice that it was missing, and why didn’t they ask about it immediately?
Or maybe they asked, and Stefanoni explained that she did perform the test?




On several dates, several times, depending what information you are talking about.



If the defence is foolish, it’s not someone else’s fault. But I seriously doubt the defence was foolish. This defence was rather good and they got all the information they wanted whenever they actually wanted to have it. When they wanted to play games and rise pretexts instead, they did so.

I always remark that you don’t understand the term ‘discovery’ in this system. Discovery means that the defence experts are allowed unfettered access during the investigation, they put their explorer’s helmet on and they to do their research. But they need to actually do their research, they are not supposed to wait for the prosecution to build defence arguments, or to fetch and bring them the material for their research arguments.

The prosecution has a duty to bring defensive arguments when they find elements that they deem they are actual exculpatory evidence, they are not expected to build specious defensive arguments based on irrelevant findings or pretexts.

Moreover in the Italian system the defence not only is not directly provided the documentation (the documentation is only deposited at the chancellery) but in order to have a copy of documentation, they also need to pay to have them (and the payment is not an irrelevant fee: at that time it was something like 70 euros (maybe more) for each support, such as CDs, there was a high fee for paper documents etc.). You may dislike this feature of the system, it’s a legitimate opinion. But it’s an opinion and here we are talking about facts.



No they are not infinite; but I’m not asking for infinite series, I’m asking for one, likely or plausible substance, or in alternative, a substance whose presence has a corroboration.
I am also asking for a dynamic, which must be also likely and probable.



I’m sorry but I think this is a rambling away from logic. Frankly I don’t even understand it. Blood getting into moisture? (what does that mean?) I agree instead with Massei when he says there are obvious indication of a cleanup, even just when you look at at bathmat (completely soakad with water) with 10+ diluted stains on it lying on a clean floor: it means cleanup. Or when you see an isolated footprint in blood whith no trail of prints leading to it, and no source around for it (there is no ‘flat surface’ where someone has stepped, as Hellmann maintains – and if there was, it had been cleaned). This means cleanup. Or even when you notice that one of Rudy’s bloody shoeprints in the trail was missing, it was revealed only by the luminol: how didi t disappear? Or even just when you notice there are three towels soaked with blood: what purpose would you use a towel for, when you have liquids poured around, if not drying up or cleaning up the liquid?



I can’t prove? It has already been shown that these prints are compatible with Amanda and Sollecito’s. Do you consider this a probable random event? I can’t prove they were made at the same time? But where’s the logic in this? In order to explain they were made in two or three separate events, I would need two or three scenarios instead than one! It would be a multiplication of improbability, the improbablity of having an isolated print positive to luminol would be multiplicated for all the times this happened. The isolated prints have features that make them very peculiar and improbable, they have a very strong analogy (they have an incredible analogy with the bloody bathmat prints too), a single event, a single explanation for all of them is logically the most probable scenario.

There is no ‘falsifier’, because literature flatly says it’s not true that TMB is a falsifier if the luminol stain is sufficiently diluted.

Finally, it just makes no sense to say the prints are meaningless people walked there after the murder: nobody walked there barefoot, nobody walked there with wet bare feet, nobody walked there hopping or dragging a towel so to produce isolated footprints; maybe you also like to assert that someone stepped with wet feet in Amanda’s room.


Caught doing what? Lying about the TMB test? When Sara Gino pointed it out in court perhaps? Or lying about the quantification of 36b? Stefanoni lied about the quantity and the reason for using a different machine...Or lying about the control data sheets? Has the prosecution ever found these missing items? They seemed to be having difficulty putting their hands on these in Hellmann's court. The Italian SC lies? No need to go past the cover page...every single judge and even the secretary lies and overstates their qualifications by calling themselves "Doctors"...when they are NOT DOCTORS...what that makes them is self important liars...dishonest and stupid for trying to pass themselves off as doctors when they in fact have no qualification of a doctor in the least.

Please stop with the lame "they could have attended the tests" excuse. Automatic records are kept inside the machine via electronic data files...this is why all scientists except the Italians apparently automatically turn over these files...another dishonest excuse that indicates purposeful corrupt action rather than simple sloppy stupid mistakes.

No prints are proved to be compatible with anyone. But please remind us all who was required to provide reference samples for these comparisons...PS this is just another failure of the Italians that after you honestly answer can only make you all look more and more foolish. Go ahead...AK, RS provided samples...who else? RG..OK, I gave you three...who else?
 
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And do you agree with Judge Massei who wrote about it in his motivations report?


He almost cleared things up but he didn't specify when the postal police arrived in relation to when they called so its not clear as a bell. So as you or someone else pointed out, it appears to be yet another issue that people can argue endlessly about.

I was curious to hear what Machs take was on it since he claims to know so much about the case and speaks Italian
 
Hey Charlie Wilkes,
As you are close to the Defence,
do you know if ANY of the samples collected and that show DNA from Rudy Guede
also have the DNA of 4 others too, as that bra clasp that supposedly has Raffaele Sollecito's DNA on it did?

No, I don't think so. A number of samples from the murder room showed Guede's DNA mixed with Meredith's, but I don't believe there were any unidentified contributors.
 
He almost cleared things up but he didn't specify when the postal police arrived in relation to when they called so its not clear as a bell. So as you or someone else pointed out, it appears to be yet another issue that people can argue endlessly about.

I was curious to hear what Machs take was on it since he claims to know so much about the case and speaks Italian

Actually, it is clear as a bell. Massei just didn't make it clear in his report, because it's not favorable to the prosecution. Moreover, while the original claim got a lot of media coverage, the debunking of the claim got no media coverage except Raffaele's hometown paper.
 
I know how it is used in the forensic literature.

No. You don't. Sensitivity is the ratio of false negatives per true positives. If a test has a sensitivity of 1:20,000, this has nothing directly to do with the "dilution" of the substance being tested. It actually means that for every 20,000 samples tested where the substance being tested is truly present (i.e. blood in our case), one will falsely test negative.


Let's try one, then:

http://projects.nfstc.org/workshops - Evaluations of premuptive tests

Tobe, Watson, Nic Dae - Evaluation of Six Presumptive Tests for Blood,
Their Specificity, Sensitivity, and Effect on High Molecular-Weight DNA
- Journal of Forensic Science, January 2007


The almost-amusing thing here is that you don't know why you're wrong. Unfortunately, you've made the same mistake as many, and that's to conflate Hemastix testing with TMB testing.

There are two types of TMB testing. There's a "quick and dirty" type, which is Hemastix. Hemastix are card strips with a patch of reagent on the end. They were developed for the analysis of blood in urine, and are still used for this purpose. However, forensic scientists have discovered that they can also be used as a quick presumptive test for blood.

There is a second, full form of TMB testing. This is the one that is recommended to be conducted on samples that show a presumptive positive under Luminol. Not the Hemastix test. The full TMB test is a two-step process, which consists of first adding the TMB reagent to the sample, then adding hydrogen peroxide. This two-step approach is critical because it allows for the screening out of virtually all other oxidants: if the sample reacts to the first step, it should be considered inconclusive and thus a negative. If, however, the sample does not react to the first test but reacts to the second, then it's highly likely that haemaglobin constituents are present.

This second test is easy to carry out in the field - although admittedly not quite as easy as rubbing a hemastix strip on the sample. The full TMB test is highly specific to blood. That is precisely why it is the test that is recommended to be conducted after a positive Luminol result.

Here, for your information and education, is the difference between the simple (but low specificity) Hemastix test and the full (and high specificity) TMB test:

Hemastix:
http://www.nfstc.org/pdi/lab_manual/Linked Documents/Protocols/pdi_lab_pro_2.17.pdf

TMB:
http://www.nfstc.org/pdi/lab_manual/Linked Documents/Protocols/pdi_lab_pro_2.19.pdf


For this educational service, there is no charge.


PS: Please, please try to learn the science properly before posting again. It's embarrassing otherwise.
 
No. You don't. Sensitivity is the ratio of false negatives per true positives. If a test has a sensitivity of 1:20,000, this has nothing directly to do with the "dilution" of the substance being tested. It actually means that for every 20,000 samples tested where the substance being tested is truly present (i.e. blood in our case), one will falsely test negative.

I think you're mistaken about the definition of sensitivity, LondonJohn. I can't find a formal definition, but I perused several papers and found nothing to back up your view.

Here, for example, is a product-brief-like thing from Blue Star.
http://www.bluestar-forensic.com/pdf/en/Watkins_Brown_luminol_BS.pdf

Under the heading "Luminol and Blue Star Sensitivity Testing," the authors walk you through their sensitivity test procedure. There’s not a word about false positives. It’s clear they consider sensitivity the weakest solution/highest dilution that produces a positive result.

Here's a paper by the Swedish National Laboratory of Forensics.
http://www.imprimus.net/PDF Files/D...ood - Interference and Effect on Analysis.pdf

The authors consider false positives a matter of selectivity -- not sensitivity. Again, there's no formal definition of sensitivity, but it's implied throughout that sensitivity is a function of blood dilution.

A snippet with that implication:
"Under laboratorial conditions CL was detected from luminol treated stains of the used hemoglobin solution (corresponding to blood) diluted up to 5•106 times. A comparably high sensitivity of the luminol test has been reported in other studies [22]."

If your definition is correct, google seems to be telling me a lot of people in the forensic world use the term wrong.
 
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