Vixen calls Bruno-Marasca wrong and incompetent in their evaluation of the DNA evidence, and then Vixen applies some arbitrary example of the number of alleles needed, in law, to be identified for a positive match. Vixen's claim is that Bruno-Marasca are incompetent for going beyond this (acc. to Vixen) simple guilt-marker.
To this, from Section 4.1 onwards, Bruno-Marasca write what the issues really are in this case. First and foremost, that when there's a rush to judgement because of, "the international nature of the story," it makes it all the more important to adhere to international Forensic-DNA standards..... because the world is watching.
Bruno-Marasca then go on (Sec 4.2ff) to show that the Nencini trial simply did not follow anything resembling the Scientific Method in evaluating the forensics.
In Sec 6.1 Bruno-Marasca start a discussion on the "trustworthiness of the evidence". In the section, they pair this trustworthiness, or lack of same, with a "motive" which both matches that evidence and converges on it. Their assessment of that is:
But back to the issue Vixen continually raises and refuses to engage in any discussion about - except to repeat the factoid about allele-level being the sole, revealing issue.
To this, Bruno-Marasca engage FULLY in Section 7 the real discussion a court should be having, one that the Nencini court did not have - therefore M/B annuled the Nencini verdict:
- a judge cannot substitute himself as a supra-expert over and above the real, scientific experts
- with that said, the judge must still sort out the conundrum of competing experts who often argue polar opposite things
- in sorting that out, the judge cannot simply rule in a vacuum as-if the judge was the sole arbiter, the judge must refer to some outside expertise acc. to "the bridging rule", which finds it's most concrete rendering from, "Section 1, no. 31456 of 21/05/2006. Franzioni, Rv. 240764".
In Section 7.1 Marasca-Bruno then apply all this to the Nencini verdict in front of them. M/B first criticizes Nencini for not even trying to make his DNA judgments according to outside, scientific considerations.
Marasca-Bruno go on to say that Nencini's errors in the forensics include:
- mistaking compatibility with identity
- failing to take into account the shortcomings of the investigation-collection process of the evidence
- "Taking into account such considerations one really cannot see how the results of the genetic analysis – that were performed in violation of the recommendations for the protocols regarding the collection and storage – can be considered endowed of the characteristics of seriousness and preciseness."
Bruno-Marasca make considerable mention of the problems associated with improper storage of evidence. This alone challenges the "repeatability" issue required by the scientific method, so that the same item of evidence can produce the same result, thus bolstering confidence that it is meaningful, and not the result of a false positive. In the way the Kercher case was handled, this is totally absent, so says Bruno-Marasca (citing the Conte-Vecchiotti report).
The fate of the bra-clasp as yielding useful, repeatable evidence is cited.
Back to Vixen's point of the number of alleles. Bruno-Marasca then cite the Low Copy Number issues, meaning that it was not possible to repeat the amplification of the samples - and the protocols in the field require two and sometimes three repeats:
So Vixen can quote the number of alleles all she wants. The issue she'll avoid like the plague is the other issue more central to the scientific method itself. Repeatability.