The Trials of Amanda Knox and Raffaele Sollecito: Part 29

[Numbers]

The cells are very different. I'm not really up to speed with how you handle a dried blood spot to get the information as I'm used to handling whole liquid blood, but the cells are there in the blood spot and it should be possible to reconstitute it so as to allow some analysis.

Human red cells are about twice the size of cat red cells. There are also significant differences in the white cells, especially the eosinophils. It's not rocket surgery.

The blood (cat or human) may have been one or two days old by the time the police saw the traces. I don't know if any samples were inspected under a microscope.

Antisera may have been used to distinguish human, cat, and dog blood, but no materials and methods, or dates of testing, or actual data were given to the defense; only the (alleged) results of positive or negative reactions to "antibody" for human, cat, or dog.

Sollecito's consultant, Adriano TAGLIABRACCI, testified as follows (translated):

[/QCONSULTANT- I think it was extracted from the mattress so if the mattress… if a human slept there they would have left human epithelial cells on it, going back to the epithelial cells of the other… she left the epithelial cells for which there was a negative result for anti-human because that serum is used on the blood but there were however epithelial cells which had given a positive result to the next quantization: I repeat desquamated epithelial cells on the mattress, this is probably the reason but if I were to be challenging and to do my duty as the technical consultant for the Defense I could also say “there has been a contamination in the laboratory, human DNA has been introduced into the tube where the quantization was made”, uh because I cannot exclude that seeing that…

The conjectures include that the surface under some of the alleged cat blood traces had human epithelial cells that did not react with the human antisera (to blood[?]) or there was contamination to account for the positive DNA amplification under PCR.

The source includes a video from the police search. There are (supposedly) large-diameter traces (difficult or impossible to see in the poorly lit video) on the steps which the police saw and marked by chalked or inked circles. Some of these traces from the steps were negative for blood by TMB but positive for human DNA. The traces in the downstairs flat are, in contrast, smaller and clearly visible under the video and room lighting.

Source: http://www.amandaknoxcase.com/blood-evidence-downstairs-apartment/

 

[Numbers]

A good source of information is a 2009 article in Forensic Science International by Virkler and Lednev. IIRC they classify HemaTrace as presumptive. IMO it is confirmatory that the substance is hemoglobin but not that it is human. I do not recall when the RSID test for glycophorin A was first introduced, but I am pretty sure that it was before 2016.

I did find this Virkler and Lednev article, but it mainly addresses use of Raman spectroscopy for the ID of semen stains.

http://www.forensic.sc.su.ac.th/seminar/seminari53/ref/52312334.pdf

My original question was, essentially, what methods and materials Stefanoni used, or could have used, to reliably forensically distinguish human, cat, and dog blood stain traces in November, 2007 or later.

Since in her report to the defense she apparently did not list any methods and materials, but only final results, of her "antibody" tests that allegedly found the blood stains downstairs to be from cat. Sollecito's DNA consultant believed she may have used antisera to blood, although he did not witness the testing (the date of which is apparently unknown except to Stefanoni and her colleagues).

The peculiarity of testing blood samples for human DNA when antisera results indicate that the blood is from cat was noted by the defense consultant. I suspect that the antisera testing, if indeed done, was conducted after the DNA testing as a justification for the police and prosecution not providing the DNA profile results for the downstairs flat blood traces.

Of further interest, Stefanoni did not indicate the blood traces from the light switch (two samples) as "cat" (or any other non-human species). Samples from these two traces were subjected to DNA quantification by Qubit Fluorometer rather than by quantitative PCR, on Nov. 6, when Stefanoni rather mysteriously switched quantification methods (due to alleged equipment malfunction). Each sample was quantified as "too low" and thus potentially contained no DNA; however, they were apparently DNA profiled and the profiles suppressed. The light switch in question was located on a wall in the "sitting room". Giobbi testified that the blood traces were the result of a cat with a bleeding ear jumping against the wall. I'm not aware of any further information on the light switch blood traces.

 

[Chris_Halkides]

quick search gives this...

For example in humans the percentage of glucose in the red blood cells is 42%, whereas 58% of the glucose is situated in plasma. In cats (less and smaller red blood cells) there is only 7% of the glucose in the red blood cells and the majority of about 93% of the glucose is located in plasma.

Hi Rose, That is quite interesting, but I don't think that one could use this difference in a forensic setting. The size of the RBC (thank you, Rolfe) might be helpful if one could rehydrate presumably dry cells without lysing them (I can see a possible problem involving osmotic stress, but probably someone has worked this out).

Hi Numbers, There are two papers from these two authors that year. The one I was thinking of is Virkler K, Lednev IK, "Analysis of body fluids for forensic purposes: from laboratory testing to non-destructive rapid confirmatory identification at a crime scene." Forensic Science International 2009 188(1-3):1-17 DOI: 10.1016/j.forsciint.2009.02.013.
PMID: 19328638. Link to abstract at PubMed here.

 

[Numbers]

Hi Rose, That is quite interesting, but I don't think that one could use this difference in a forensic setting. The size of the RBC (thank you, Rolfe) might be helpful if one could rehydrate presumably dry cells without lysing them (I can see a possible problem involving osmotic stress, but probably someone has worked this out).

Hi Numbers, There are two papers from these two authors that year. The one I was thinking of is Virkler K, Lednev IK, "Analysis of body fluids for forensic purposes: from laboratory testing to non-destructive rapid confirmatory identification at a crime scene." Forensic Science International 2009 188(1-3):1-17 DOI: 10.1016/j.forsciint.2009.02.013.
PMID: 19328638. Link to abstract at PubMed here.

Thanks, Chris.

 

[TomG]

Ricardo's room

What vexes me the most is why Rudy would want to implicate someone as being downstairs in the first place if he wasn't there himself. Rudy's first mention of noises downstairs came from his prison diary in 2007 when he may have been trying to implicate one of the boys who rented the apartments. It resurfaces again in his March 26 2008 statement but by that time the boys would have had their alibis well and truly established, so he is obviously trying to suggest K&S were downstairs while he was tending to Meredith. However, in Rudy's own heroic narrative of events he doesn't suggest that K&S went downstairs when he was preoccupied with Meredith. There is nothing to be gained by suggesting that anyone was downstairs in the slightest. I don't see what leverage the claim would have in implicating anyone else in the crime.

I must admit I was a bit freaked out when I saw the blood on the steps in the video, some of the circular traces seem to be over 8cm wide in some cases. How can it maintain a circular shape like that without dispersing? Or is that not blood I'm looking at. Bonassi's room is a mess, he said it was "perfect" so why would he lie? His duvet is totally tossed about, can a cat do that?

I'm equally perplexed also by Ricardo's room. The guys pissed on his floor but there is an outline left that is noticeable in 18:31:24 that is undoubtedly red. So it seems to me that the guys pissed on the floor and either the cat or Rudy bled on the still wet urine with the blood dispersing to the edges as the urine dried resulting in the odd linear markings much the same as the steps. There is also what appears to be blood drops in frame 18:30:31. Position 18:32:27 shows the door has been kicked in to gain access, you can briefly see it earlier at 18:30:03. So if it is blood on the floor as I suspect, the cat must have booted in the door and bled on the urine. Either that or what I'm looking at isn't blood. If it's red and it isn't blood, what is it?

Hoots

 

[Stacyhs]

Actually, it wasn't Guede who claimed this it was some guy called 'Free Rudy Guede' on Twitter. Certianly a chair had been pulled to the window and one can speculate that someone did so to look out of the bathroom window. What did it overlook? The car park.

Someone was was definitely in there - either one of the three - as I can't imagine Mez did anything more downstairs than feed the cat or water the plants. There wasn't anyone for her to frolic on Bonassi's bed with.

The entire downstairs is below the car park.

Which car park is Vixen referring to? The garage across the street or the parking area for the cottage itself?

I have been unable to find a floor plan of the downstairs apartment so I don't know where the bathroom was located.

I'd also like to know what evidence there is that "a chair had been pulled to the window" in the boys' bathroom. If so, one can also 'speculate' that it always sat in that same position.

I do have to wonder why anyone would quote some unknown Free Rudy Guede twitterer making a claim that is entirely unsupported by any evidence.

 

[Numbers]

What vexes me the most is why Rudy would want to implicate someone as being downstairs in the first place if he wasn't there himself. Rudy's first mention of noises downstairs came from his prison diary in 2007 when he may have been trying to implicate one of the boys who rented the apartments. It resurfaces again in his March 26 2008 statement but by that time the boys would have had their alibis well and truly established, so he is obviously trying to suggest K&S were downstairs while he was tending to Meredith. However, in Rudy's own heroic narrative of events he doesn't suggest that K&S went downstairs when he was preoccupied with Meredith. There is nothing to be gained by suggesting that anyone was downstairs in the slightest. I don't see what leverage the claim would have in implicating anyone else in the crime.

I must admit I was a bit freaked out when I saw the blood on the steps in the video, some of the circular traces seem to be over 8cm wide in some cases. How can it maintain a circular shape like that without dispersing? Or is that not blood I'm looking at. Bonassi's room is a mess, he said it was "perfect" so why would he lie? His duvet is totally tossed about, can a cat do that?

I'm equally perplexed also by Ricardo's room. The guys pissed on his floor but there is an outline left that is noticeable in 18:31:24 that is undoubtedly red. So it seems to me that the guys pissed on the floor and either the cat or Rudy bled on the still wet urine with the blood dispersing to the edges as the urine dried resulting in the odd linear markings much the same as the steps. There is also what appears to be blood drops in frame 18:30:31. Position 18:32:27 shows the door has been kicked in to gain access, you can briefly see it earlier at 18:30:03. So if it is blood on the floor as I suspect, the cat must have booted in the door and bled on the urine. Either that or what I'm looking at isn't blood. If it's red and it isn't blood, what is it?

Hoots

Thanks for pointing out some of the mysteries of the downstairs flat.

I think that the broken bedroom door was broken by the police (most likely?) or it broken before the police came in (unlikely).

The traces most readily observed on the outside stairs may be what appear to be the markings (crayon, chalk, ink?) drawn by the police around the actual apparent blood traces. At least, that is what I think those outlines are.

 

[Numbers]

I have been searching online for information or a supplier of antisera for animal (cat) blood, especially for forensics.

Here is one in the US, Serological Research Institute, Richmond CA:

www.serological.com/sera-antisera.php

Product "A422

Description – Freeze dried antiserum for use in forensic labs Absorbed to balance specificity with titer. Positive controls a must. Recommended for use with crossover electrophoresis. Gel Diffusion titers are frequently low. Gel staining a must."

The test requires a postive control, Product "A421

Description – Freeze dried whole normal serum for use as control in tests for species origin."

Of interest, the vendor indicates some aspects of the method required.

 

[Methos]

Which car park is Vixen referring to? The garage across the street or the parking area for the cottage itself?

I have been unable to find a floor plan of the downstairs apartment so I don't know where the bathroom was located.

I'd also like to know what evidence there is that "a chair had been pulled to the window" in the boys' bathroom. If so, one can also 'speculate' that it always sat in that same position.

I do have to wonder why anyone would quote some unknown Free Rudy Guede twitterer making a claim that is entirely unsupported by any evidence.

Floor plan


The "a chair had been pulled to the window" nonsense is apparently based on the Nov 2nd crime scene video beginning at 7:26 min (Nov 2nd, 2007 16:40:33)...

It is this window:

The "Free Rudy Guede" account disappeared from twitter shortly after Guede's "official" facebook and twitter accounts went offline...

 

[Vixen]

Which car park is Vixen referring to? The garage across the street or the parking area for the cottage itself?

I have been unable to find a floor plan of the downstairs apartment so I don't know where the bathroom was located.

I'd also like to know what evidence there is that "a chair had been pulled to the window" in the boys' bathroom. If so, one can also 'speculate' that it always sat in that same position.

I do have to wonder why anyone would quote some unknown Free Rudy Guede twitterer making a claim that is entirely unsupported by any evidence.

Which car park? The one Guede supposedly threw the rock from.

For goodness sake, BiWi has reproduced the photo of the barred window below Filomena's room often enough. (=That small window is the boys' bathroom.) It does indeed look towards the car park but being spilt level you probably would need to stand on a chair to look into the car park, it being semi-basement.

 

[Vixen]

Floor plan


The "a chair had been pulled to the window" nonsense is apparently based on the Nov 2nd crime scene video beginning at 7:26 min (Nov 2nd, 2007 16:40:33)...

It is this window:
[qimg]http://www.injusticeinperugia.org/hendry18.jpg[/qimg]

The "Free Rudy Guede" account disappeared from twitter shortly after Guede's "official" facebook and twitter accounts went offline...

Do you think 'Free Rudy Guede' was Rudy himself?

 

[Mr Fied]

Floor plan


The "a chair had been pulled to the window" nonsense is apparently based on the Nov 2nd crime scene video beginning at 7:26 min (Nov 2nd, 2007 16:40:33)...

It is this window:
[qimg]http://www.injusticeinperugia.org/hendry18.jpg[/qimg]

The "Free Rudy Guede" account disappeared from twitter shortly after Guede's "official" facebook and twitter accounts went offline...

Which car park? The one Guede supposedly threw the rock from.

For goodness sake, BiWi has reproduced the photo of the barred window below Filomena's room often enough. (=That small window is the boys' bathroom.) It does indeed look towards the car park but being spilt level you probably would need to stand on a chair to look into the car park, it being semi-basement.

What difference would standing on a chair make if the window is lower than the car park level?

 

[RoseMontague]

What difference would standing on a chair make if the window is lower than the car park level?

None. It doesn't "overlook" the car park.

 

[Mr Fied]

None. It doesn't "overlook" the car park.

Thanks Rose, I thought it was just me not understanding it correctly.

 

[LondonJohn]

Thanks Rose, I thought it was just me not understanding it correctly.

Oh no - be assured that it's not YOU who's not understanding it correctly.............

(Heaven's sake: Vixen needed look no further than the video still reproduced in the post before hers to see all the evidence she needed (though of course she should have known it already). But no...)

 

[LondonJohn]

But at least we're not getting that rock referred to ridiculously as a "boulder", so.... y'know..... baby steps and all that.......

 

[TruthCalls]

None. It doesn't "overlook" the car park.

Also, the seat of the chair is lower than the top ledge of the bathtub. Why would someone stand on a chair and then lean over the bathtub to look out the window when it would be easier, quicker and give you a better vantage point (to view a dirt bank) by just standing on the tub?

 

[RoseMontague]

Also, the seat of the chair is lower than the top ledge of the bathtub. Why would someone stand on a chair and then lean over the bathtub to look out the window when it would be easier, quicker and give you a better vantage point (to view a dirt bank) by just standing on the tub?

Lol, yes. Standing in the tub would give you a better view, at least you are looking up towards the car park and might be able to see the front grill of a car right up to the edge of the railing. If you're lucky.

 

[LondonJohn]

Also, the seat of the chair is lower than the top ledge of the bathtub. Why would someone stand on a chair and then lean over the bathtub to look out the window when it would be easier, quicker and give you a better vantage point (to view a dirt bank) by just standing on the tub?

Erm, will you please stop using elementary logic and solid reasoning in your arguments on this matter. It's perfectly obvious (using bizarro-world rules) that any rational person would have used that chair in front of the bath, rather than stand on the higher and closer-to-the-window bath rim itself, in order to look out onto a car park that it was impossible to see whether one was standing on the bath or the chair.

Do keep up

 

[Methos]

Do you think 'Free Rudy Guede' was Rudy himself?

No.