Ok. It is clear that the top of skeptigirl's game is poisoning the well of anything that disagrees with her predetermined conclusion. It is clear that she believe that her sources are more objective than other sources, though I do not see that has been established. But let us look at what the other side say about those matters which she believes prove the case is a miscarriage of justice
1. The quality of the DNA evidence.
a.The knife.
The prosecution states that the knife found in Sollecito's home had traces of Knox's dna on the handle.That is not disputed and is explained by the fact that she regularly cooked in his apartment. Fair enough.
The prosecution states that a small trace of Kerchner's DNA was found on the knife. This was established by tests done in the lab and under the supervision of Dr Stefanoni, who is an internationally respected forensic scientist based in Rome. In July
Both Dr. Renato Biondo, the head of the DNA Unit of the scientific police, and the Kerchers’ own DNA expert, Professor Francesca Torricelli, provided independent confirmation that this forensic finding is accurate and reliable.
They did not dispute the DNA was on the knife: they did not dispute it was Kerchner's. Socellito, when told of the finding, said that the reason the DNA was there was because on one occasion, while Kerchber was cooking at his home, he accidentally pricked her with the knife. But Kerchner had never been to his flat so that was really not very helpful.
There are two parts to the defence case:
There was not a big enough sample to allow for a re-test. That is certainly a problem, but it is not enough to overturn the finding. Dr Stefanano is an internationally respected forensic scientist who led the forensic team.She is based in Rome. She is experienced and so is her team, who also came from Rome. There is no reason whatsoever to presume that she had any bias against Knox, and none to indicate that she perjured herself. One may regret the lack of a retest but it does not seem that the defence are arguing that the dna was not there at all. And indeed that would need quite a conspiracy with no obvious motive. Dr Stefanoni found odd marks on the knife which she considers indicate that the knife was vigorously cleaned. If this is the case then the small sample size is not that surprising: are we to ignore evidence in these circumstances? If it is all we have then perhaps: but it isn't
The second part rests on the possibility that the knife was contaminated. That is, on the face of it, more plausible. It could have been contaminated in the course of the investigation or it could have been contaminated in the lab.
The testimony shows that the investigators who found the knife were a different team from the one that searched the cottage: the knife was found and put in a plastic bag, which was then put into a box. There does not seem to be any possibility of contamination at that stage
Dr Stefanoni denies that contamination happened in her lab. "Well she would, wouldn't she" might be in play. And this is possible. She has a reputation to defend and it is plausible that she would wish to state that the procedures and precautions taken were of a high standard. Dr Stefanoni addressed this in her testimony. She said that there has been no instance of contamination of this sort in her lab in the last 7 years. She pointed to the fact that no DNA from any of her team was found on any of the objects tested: if contamination was a problem it would be curious that only Kerchner's DNA was transferred: sloppy procedures would be more believable if there were other contaminants from lab staff, for example: but there weren't.
The defence case rests on a possibility which exists in every case of forensic evidence of this kind: and for which there is no evidence at all. Anything
can happen. The jury has to judge whether it
did happen. That necessarily rests on the case presented and the credibility of the witnesses presenting it. That is true in any court in the world. There is nothing flawed in it.
b. The bra clasp.
The prosecution say that Socellito's DNA was found on Kerchner's bra clasp. Once again this is not disputed. The sample was larger and firmly attached to the clasp. The defence case rests on the fact that the clasp was not collected till a long time after the event: that in the meantime it lay about in the room where the murder happened: and that it was contaminated during that period; or later, in the laboratory.
Once again the question of contamination in the laboratory depends on the view one takes of the competence of Dr Stefanoni and her team: so naturally the defence have questioned that and the witness has testified as to the procedures adopted etc. Again this comes down to competence and, aside from this case, there does not seem to be anyone who is denying that Dr Stefanoni is respected in her field.
The time delay is important. But it is only important if one can show a source for contamination during that period: by itself it is not enough. The prosecution point out that dna is often collected long after the events it relates to and is regularly accepted as evidence: so the defence need to show that this delay led to contamination: not just that it was there
According to testimony the only source for Socellito's DNA in that house was a cigarette butt in the kitchen. So it seems that in order for contamination to occur before it got to the lab it would have to have been transferred from that; but again, no biological traces from any of the investigating team were found. If passive transfer of DNA were easy and the procedures sloppy it seems reasonable to suppose that other contamination would be in evidence. Perhaps there is a reason why that is not the case and someone will explain that. If it is true then I presume the defence will have shown that in spades to the jury, because it is rather important
Again, anything
can happen: and it is the defence's job to try to show that things helpful to their case
did happen. As it is the prosecution's job to show that they did not. It is for the jury to decide on the basis of the evidence presented and their judgement of the credibility of the witnesses. That is how courts work. If the jury was to accept uncritically every
possible explanation which tended to exonerate the defendant we would never get any convictions at all. The test is "beyond reasonable doubt": but that does not mean beyond any possible doubt and the jury is not expected to suspend their critical faculties. They are expected to use them.
As it happens the DNA evidence on the knife and the bra clasp were not the main bits of evidence which led the judge to commit Knox and Socellito for trial. This is shown in the part of his detailed judgement after Guede's conviction which I linked above. A major plank underpinning that decision was the footprint evidence. The judge could not ignore that and neither should we.
I will come back to that if no-one else does but I have no time at present
