Mixed DNA in the Shared Bathroom

Rudy Guede Statements About The Bathroom

German prison diary:[1]

I took a towel from her bathroom, but in less than a minute it was all soaked. I took another, but it was no use.

I left the house in shock. I was outside, but didn’t know where to go, seeing still all that blood. It was all so red. I thought of going home. I had wet trousers and tried to cover it with the sweatshirt. There were a lot of people in the street, in Piazza Grimana. There were some guys still playing basketball even though it was dark.

Blood Discovery November 2

Testimony of Fabio Marsi page 7 (postal police) about seeing the bathroom

Bongiorno: When Amanda took you to see the patches of blood in the bathroom, was she alarmed? Were they noticeable patches, or was it something less noticeable?

Marsi: No, it’s not like there was a, a particularly thick patch, they were… a few marks left, probably, by somebody that had dirty hands, there wasn’t specifically a round patch where the blood had drained. Speaking in an imperfect Italian she said to me: “Here dirty here also below, I scared, I didn’t touch anything”, she said to me.

Massei: Excuse me, where were these traces of blood?

Marsi: On the washbasin, on the faucet and also on the bathmat that was below the washbasin

Meredith Kercher's bathroom November 2
Meredith Kercher’s bathroom November 2

Sloppy Evidence Collection in the Bathroom

The crime scene video below has been subtitled and you can hear the investigator saying they washed the sink within 2 hours of the body being discovered. Why?

Gioia Brocci, photographic agent of the Questura of Perugia, collected the evidence samples in the bathroom that was shared by Amanda and Meredith. Three of the samples showed Amanda’s DNA mixed with Meredith’s blood. The prosecution tried to insinuate that these findings are incriminating.

Meredith’s blood was visible in several areas in the bathroom. Rudy Guede used the bathroom to quickly clean himself up. When he did this he left behind small amounts of Meredith’s blood. As stated above, three of these samples were mixed with Amanda’s DNA. This is completely understandable because the bathroom was used daily by Amanda.

To put this in perspective, think about your own bathroom. Swabbing your bathroom sink in the bathroom that you use daily would unquestionably yield your DNA. When Gioia Brocci collected the samples from the bathroom she swabbed large surface areas to clean up the blood. When doing this she also wiped up Amanda’s DNA in the process. When collecting samples, Brocci actually advanced the mixing process. She used the swabs like a cleaning rag.

It was unknown at the time but the drop of blood on the faucet belonged to Amanda. This blood was not mixed with any other DNA. The small amount of blood on the faucet most likely came from an irritated ear piercing. Brocci collected this sample before she collected the other samples on the sink, toilet, wall and bidet.

The video below shows the samples being collected in the bathroom. When watching the video look for these important details.

1. Brocci wiped Amanda’s drop of blood off of the faucet before she collected the other samples on the sink, toilet, wall and bidet. Watch her thumb. Brocci kept her thumb down and rubbed her thumb repeatedly over the sample.

2. Brocci did not change her gloves after she collected each sample. (see photos below) Watch as she collected the next sample after the faucet. Once again, she put the same thumb down into the sample that she was collecting. Keep in mind, it was unknown at the time, but the sample from the faucet contained Amanda’s blood. She had now repeatedly rubbed her thumb in Amanda’s blood and then onto the next sample.

3. When Brocci collected the samples from the sink and the bidet, she used a wiping motion and wiped multiple surfaces with the same swab. She was collecting Amanda’s DNA from Amanda’s own bathroom as she was collecting Meredith’s blood samples. Not only was she collecting Amanda’s residual DNA, she was mixing it together with Meredith’s blood.

After watching the video you can clearly see that the mixed DNA that was collected from the bathroom is not incriminating in any way. The DNA samples can be used to show that Meredith’s blood was present in the bathroom. The evidence can also be used to show who possibly used the bathroom. The fact that these samples are mixed, means nothing.

Brocci advanced the mixing process with her evidence collection procedures. She wiped large surfaces when she collected the samples. She did not change gloves after collecting Amanda’s blood off of the faucet or after collecting any of the other samples. Both of these procedures undoubtedly mixed the DNA.

The video also shows that Brocci never changed her gloves when she collected the samples from the bathroom. The images below were taken from the same video. The crime scene videos are very choppy. The video is stopped between each sample presumably so Brocci can put the swabs into evidence containers.

Look at the images of the gloves below. Look at the glove on Brocci’s right hand. There is a fold in that glove that runs across the back of her hand. In the last 3 images, notice the area of the glove that is rolled up at her wrist. The glove is rolled the same way in all 3 images. One area dips down from the rolled section. It would have been impossible for Brocci to change gloves between each sample. There is no way that each time she put a new glove on her right hand that the glove would fold the same way across her hand and also roll the same way at her wrist.

Brocci wipes Amanda’s blood off of the faucet. In all of the images below, you can clearly see the same fold going across the back of Brocci’s hand.

Brocci wipes Amanda’s blood off of the sink. Note that her thumb is down below the swab making contact with the surface of the sink. That is the same thumb that had just made repeated contact with Amanda’s blood on the faucet.

Brocci wipes a blood sample off of the wall. Note how the glove is rolled at the wrist. You will see that the glove is rolled the same way in the each of the photos below.

Brocci collects a sample from the toilet. The hand is facing the other direction but notice that the glove is rolled at the wrist just like the glove in the image above.

Brocci collects a sample from the bidet.
First on the rim…

Brocci collects a sample from the bidet.
…then near the drain using the same swab.

Hellmann Report

Why the mixed DNA traces in Meredith and Amanda’s bathroom are evidence more of police incompetence than anything else.

As we have already seen, it was Lead Officer [assistente capo] Gioia Brocci who carried out the [evidence] collection in the small bathroom near Meredith’s room on the afternoon of November 2nd 2007.She stated (ruling [of lower court], page 100) that, in that bathroom, in addition to the mat discussed above, there were traces which seemed to be of blood. She specified that they were seepages of a pinkish color, “not the red typical of blood”. She found the latter only on the faucet of the sink.

Concerning the method of collection, she said that she had done the job with a single swab of blotting paper, because “the drop upstream and the drop downstream had a sort of continuity: there were droplets on the same line, hence out of color and continuity of trickling I saw fit to collect them with a single swab” (from the hearing of 04/23/2009). Traces apparently made of blood were also present on a box of cotton swabs, on the toilet lid [tavoletta], on the light switch, and on the bidet “and there was always the upstream drop, on the rim itself and the same continuity down to the drain of the bidet, of the usual color and on the same line”. Traces were also present on the door of the bathroom, these, however, were not as if they had been mixed with water, but of a bright red color.

At the hearing of 05/22/2009 Dr. Patrizia Stefanoni, biologist with the forensic genetic section of the Scientific Police in Rome, related (ruling pp. 198 and 204) that on the light switch, on the toilet lid and on the framework of the door, the blood of the victim had been found, while the samples taken from the bidet, the sink and the cotton-swab box had displayed human blood and a mixed profile of Kercher and Knox. The sample taken from the front part of the tap of the sink, however, had revealed human blood and the genetic profile of Knox alone.

The defendants’ attorneys have severely criticized the method of collection employed on the sink and the bidet.

Footage of this procedure was shown in Court: Officer Brocci is clearly seen to run the same swab of blotting paper again and again several times, with a dragging motion, from the rim of the sink down to the drain and back, and on both sides [of the sink]. The same procedure for the bidet, where the swab – presumably a different one – is used to accurately clean the drain area. About this procedure, Dr Stefanoni observed “that apparently this might not seem appropriate for collection” but that in that specific context it was, “because of the typology of traces that were collected” which “were clearly pinkish, hence they appeared as traces definitely mixed with water and they were seemingly all of the same origin because they were seepages…a rivulet of sorts starting from above and ending in the drain”.

In her judgement it was improbable that this was a case of two DNA [samples] that were separate at the origin and which then combined in a single trace; as can be read in the ruling on page 212, this was “because of both the single location concerned and the same appearance of very diluted blood”. A statement whose generality and inconsistency need hardly be stressed, all the more so since it is in stark contrast with another statement, much more logical and convincing, made by Stefanoni herself and quoted below.

Now, it is not possible to agree with what Dr. Stefanoni claimed about the correctness of the sampling procedure of the traces on the sink and on the bidet. It is obvious even to a layperson that the two bathroom fixtures concerned, intended for personal hygiene, are a natural repository of DNA, that is released easily when washing: epithelial cells, organic fluids (sweat, saliva), hair and body hair flow swept by the water and, at least partially, remain on the ceramic surface, particularly in the area around the drain, and there they reside, short of a frequent and accurate cleaning. It must be remembered that Lead Officer Brocci had occasion to state that she had also collected (ruling, p. 100) a sample of hair on the sink, of whose genetic analysis, however, there is no mention, if it was ever performed. And on the faucet, blood was found belonging only to Knox.

The small bathroom at issue was used by the two girls, Meredith and Amanda, while the other two (Mezzetti and Romanelli) used the larger bathroom. It seems, then, wholly believable that the DNA of the two girls could be found on the fixtures of the small bathroom. In such a situation, evidence collection by means of repeatedly rubbing from rim to drain and back, on both sides with the same swab of blotting paper, is, contrary to what Dr. Stefanoni claimed, manifestly the least appropriate way to obtain a reassuring result. Surely in this manner all of the DNA present on the path was collected, creating a mixture that probably did not exist originally.

We must remember what was stated in a general sense by Stefanoni herself and written on page 221 of the ruling: it is not possible to date a trace nor establish whether one was left before another. More precisely, with specific reference to the traces on the sink and on the bidet, she stated, as can be read in the ruling on page 228 “that they were dry and it was impossible to date them or to determine if the trace attributable to Knox was left first and then that attributable to the victim, or the other way around”. Thus it seems totally irrelevant, for purposes of a decision unfavorable to Knox, that her DNA was found mixed with the victim’s DNA on the bathroom fixtures.

If, indeed, the mixture had been pre-existent at the moment of application [apposizione], it should also have been detected on the toilet lid, on the light switch and on the door framework: this did not happen, no doubt because the person who put the victim’s blood in that precise spot did not find any DNA previously deposited. Even more questionable are the genetic results from the samples taken from the cotton-swab container: according to Stefanoni (ruling p. 223) a third person could even be present, also of female sex. And this is because the alleles where very homogeneous in height, and one could think of pairings different from those attributed to Knox and Kercher, so involving other people besides those already present. An opinion shared by Dr. Torricelli, consultant for the Kercher family (ruling, page 243). Which leads one to think of the superposition of traces at different times — from the jar [barattolo] having passed through several hands — rather than a single contact by the murderer.

So we cannot agree with the relevant conclusions reached in the ruling, on page 405 et seq.. According to the first-level Court, the two defendants, stained with Meredith’s blood, are supposed to have gone into the adjacent small bathroom and washed themselves there (it will be remembered that according to the first judges the footprint on the mat had been left by Sollecito’s right foot). But if it had been so, one cannot explain why the smallest genetic trace of Sollecito was not found in the small bathroom, despite the fact that the scrubbing due to the cleansing should involve the loss of flaking cells (as we read again in the ruling). The fact that only Amanda’s DNA was found together with Meredith’s leads us to believe that the mixture was created by the Police during an inappropriate collection operation. Greater confidence could be placed in the analyses, indeed, if the collection had been made point by point and not through an insistent rubbing, repeated over different points of each fixture.

Bathroom Samples Analysed

Amanda Knox case: CSI removing a screw from Raffaele's bathroom shower. They lost interest in Meredith's bathroom once Rudy Guede was identified.
CSI removing a screw from Raffaele’s bathroom shower. They lost interest in Meredith’s bathroom once Rudy Guede was identified and couldn’t risk finding evidence of him in there. They were determined to say his print on the bathmat belonged to Sollecito.

Total Samples – 10

Samples of presumed biological traces and exhibits taken from the small bathroom (adjacent to the room where the cadaver was found–Ground floor apartment (upper).[2]

Rep.22 – Sky blue bathmat placed on the floor in front of the washbasin of interest the trace of presumed blood substance (Rep.9/F) – page 29 A.F./51 R.

Rep.23 – Sample of presumed blood substance taken from the area of the light switch. (Rep.9/A) – page 30 A.F./52 R.;

Rep.24 – Sample of presumed blood substance taken from the front surface of the faucet of the washbasin (Rep.9/C) page 30 A.F./53 R.;

Rep.66 – Sample of presumed blood substance taken from the margin of the drain of the bidet. (Rep.9/I) – page 32 A.F./117 R.;

Rep.136 – Sample of presumed blood substance taken from the transparent plastic container per cotton-flock placed on the floor of the bathroom, left side (Rep.9/B) – page 33 A.F./174 R;

Rep.137 – Drop of presumed blood substance taken from inside the washbasin (Rep.9/D) – page 33 A.F./174 R.

Rep.138 – Hair formation taken from inside the washbasin (Rep.9/E) – page 35 A.F./176 R;

Rep.139 – Sample of presumed blood substance taken from the toilet lid (Rep.9/G) page 35 A.F./176 R;

Rep.140 – Sample of presumed blood substance taken from the outer right side of the door frame, about 50 cm (19.7 inches) from the floor. (Rep.9/L – page 37 A.F./178R.;

Rep.141 – Sample of drop of presumed blood substance taken from the waste pipe of the toilet corresponding to the right wall. (Rep.9/H) – page 37 A.F./178 R.;

Expert Opinion

“And also relying on DNA evidence of a girl who lived in that room and who uses that bathroom; and to find her DNA in there…..just because somebody else brought other DNA or blood from the victim into that room — the fact that Amanda Knox’s DNA is in there is completely 100% irrelevant to this criminal prosecution. You can’t….I mean it’s just mind-boggling they could rely on that kind of evidence….” ~ Jim Clemente, retired FBI profiler on CrimeTime Feb 2014


Hellmann Report – Why the mixed DNA traces in Meredith and Amanda’s bathroom are evidence more of police incompetence than anything else – (English)

Crime Scene Photos

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