Debunking komponisto on Amanda Knox (long)

byrolf_nelson9y2nd Feb 2010118 comments


Rebuttal to: The Amanda Knox Test

If you don't care about Amanda Knox's guilt, or whether you have received unreliable information on the subject from komponisto's post, stop reading now.

[Edit: Let me note that, generally, I agree that discussion of current events should be discouraged in this site. It is only because "The Amanda Knox Test" was a featured post on this site that I claim this rebuttal of that post to be on-topic for this site.]

I shall here make the following claim:

C1. komponisto's post on Amanda Knox was misleading.

I could, additionally, choose to make the following claims:

C2. Amanda Knox is guilty of murder.
C3. The prosecution succeeded in proving Amanda's guilt beyond a reasonable doubt
C4. Amanda Knox received a fair trial

I believe claims C2 through C4 are also true; however, time constraints prevent me from laying out the cases and debating them with every single human being on the Internet, so I shall merely focus on C1. (That said, I would be willing to debate komponisto on C2, since I am curious whether I could get him to change his mind on the subject.)

To back up C1, I shall quote the following paragraph from komponisto's post, and show that this paragraph alone contains at least four misleading statements. My belief is that komponisto merely accepted propaganda from the Friends of Amanda (FoA) at face value, even though most of their claims are incorrect. Unlike komponisto and FoA, I shall cite reliable sources for my claims.

"After the murder, Kercher's bedroom was filled with evidence of Guédé's presence; his DNA was found not only on top of but actually inside her body. That's about as close to the crime as it gets. At the same time, no remotely similarly incriminating genetic material was found from anyone else -- in particular, there were no traces of the presence of either Amanda Knox or Raffaele Sollecito in the room (and no, the supposed Sollecito DNA on Meredith's bra clasp just plain does not count -- nor, while we're at it, do the 100 picograms [about one human cell's worth] of DNA from Meredith allegedly on the tip of a knife handled by Knox, found at Sollecito's apartment after the two were already suspects; these two things constituting so far as I know the entirety of the physical "evidence" against the couple)" -komponisto

Here are the four misleading statements I found:

1. "[H]is DNA was found not only on top of but actually inside her body... no remotely similarly incriminating genetic material was found from anyone else" -komponsito

Guede's dna was, indeed, found on the right side of her bra, on the left cuff of her jumper, and inside Meredith's body, as well as in other places around the house.

Raffaele's DNA was found in only two places in the house: a cigarette butt, and on Meredith's torn-off bra clasp. (Contrary to FoA propaganda, the clasp did not contain DNA from an additional "three unidentified people"). This should help you understand that DNA does not voluminously and constantly spew forth from humans in the way komponisto believes it does. (That said, there might have been more traces of their DNA had Raffaele and Amanda not cleaned the apartment the morning after the murder. Part of the reason Guede's DNA is more widespread is because Raffaele and Amanda focused on cleaning up evidence pointing to themselves, and did not have a reason to care about evidence pointing to Guede.)

Amanda's DNA was found on the handle of a certain knife in Raffaele's apartment, which Meredith had never visited. The knife blade had been recently cleaned with bleach (which destroys DNA), but hiding in a groove near the tip of the blade that the bleach failed to scrub was a sample of Meredith's DNA. The blade matched one of the two knives used to kill Meredith. When later questioned about it, Raffaele first claimed that Meredith had visited his apartment and cut herself on that particular blade. Unfortunately Raffaele was not able to back up this dubious claim that Meredith had ever visited Raffaele's apartment.

Amanda's DNA was also found, mixed with Meredith's DNA, in at least four blood spots across the apartment. One of the blood spots was in the third roommate's (Filomena's) bedroom, where the staged break-in took place. Even if, like komponisto, you bizarrely believe that DNA just gets everywhere, it's hard to explain why Amanda's DNA is mixed into that final spot of blood and why Filomena's DNA is nowhere to be seen in that blood spot, despite its being in her own bedroom. (Nor, tellingly, is Guede's DNA mixed in with those blood spots, despite the defense's insistence that he acted alone.)

2. "Supposed" Sollecito DNA? There is no meaningful controversy over whether Sollecito's DNA is on the bra clasp.

3. A bit of a nit: Meredith's DNA on the knife is more than one human cell's worth. The amount is not terribly relevant though to a Bayesian; there's no law of nature that states that, when any DNA sample gets sufficiently small, it suddenly starts to mutate to look exactly like Meredith Kercher's DNA.

4. "[T]hese two things constituting so far as I know the entirety of the physical "evidence" against the couple..." -komponsito

Here is additional physical evidence (a non-exhaustive list):

* As mentioned, blood stains with Amanda and Meridith's DNA mixed together

* Forensic analysis of Meredith's body showed there were multiple simultaneous attackers

* Luminol analysis showed that certain bloody footprints matched Amanda and Raffaele. One of Amanda's bloody footprints was found inside the murder room, on a pillow hidden under Meredith's body.

* A staged break-in: analysis of the broken glass shards indicated the window was broken from the inside rather than the outside, and was broken after the bedroom was ransacked rather than before. (The significance of this is that Knox as a roommate had a strong reason to stage a break-in to deflect attention away from herself, while Guede as an outsider did not)

* Cell phone, Internet and laptop usage records all indicate that Amanda and Raffaele lied about their activities on the night of the murder.

* Meredith's clothes were washed the day after the murder. This implicates Amanda and Raffaele in the cleanup of the crime scene.

* The post-murder cleaning in the Kercher flat, and the bleaching in the Sollecito cottage, also count as Bayesian physical evidence. The morning after the murder, Amanda or Raffelle bought a bottle of bleach at 8:30 AM, and then returned to buy another bottle of bleach at 9:15 AM, as though the first bottle of bleach had been insufficient. (Also see the Telegraph.) According to, when the police arrived, Amanda and Raffaele were found with a mop and bucket; as confirmation, note that Raffaele admitted to shuttling around a mop and bucket the morning after the murder.

There is also voluminous evidence that would generally be classified as 'testimonial' rather than 'physical' (although, to a Bayesian, the difference is fairly academic), as well as certain logical problems with the defense's theories. Since my intent is merely to debunk komponisto's post rather than establish Amanda's guilt, I will not delve further into those areas; however, see here for a good "Introduction to Logic 101" explaining some of the difficulties with the defense claims.