However those who have the most explaining to do are Rome Professors Carla Vecchiotti and Stefano Conti, the two court-appointed independent experts whose scathing report of the forensic evidence in Knox’s first appeal (later annulled) led to her acquittal and release in 2011.
In his report released earlier this week, Judge Nencini does not mince words, alternatively describing their work reviewing the forensics “clearly in error,” “misleading” and even “reprehensible.” It is not the first time. She was also cited for clamorous errors in a previous murder case (Olgiata) in which forensic samples were mixed up. Nencini’s report is bound to amplify concerns already circulating within the Italian forensic community, and could possibly even trigger an investigation.
Over the course of approximately 50 pages of his 337 reasoning report, Nencini does a thorough analysis of all the court evidence, lab data and depositions by all the forensic consultants, and essentially debunks Vecchiotti and Conti’s report. He reveals that the two experts overlooked available data, altered the meaning of forensic police statements to fit their thesis, erred in their interpretation methods and falsely claimed the technology didn’t exist to test a small trace of DNA that was later successfully tested. If you are not interested in forensic minutiae, you can stop reading now.
The harsh Vecchiotti-Conti review begins on page 195 of Nencini’s report. The possibility of contamination so hotly debated by consultants and made credible to the point of being included in the independent experts’ written report actually “has no significance” in the criminal trial, he wrote, and was “misleading.”
He categorically rules out contamination. Even in the case of the bra clasp catalogued by police but only collected 46 days later, had Sollecito’s DNA been fruit of contamination it would have been found elsewhere and on other objects taken from the scene that day, such as on Meredith’s blue sweatshirt where Guede’s DNA was found, he wrote, not just on the tiny hook of the bra clasp. He notes records show there were no other items containing Sollecito’s DNA handled that day, ruling out making laboratory contamination. Nencini accepts there may have been professional lapses on part of the forensic police, but determines that none of those oversights were so grave as to have negatively impacted the forensic analysis with regard to the case. The absence of contamination is also proven by the records of negative and positive controls performed by much-maligned forensic biologist Patrizia Stefanoni. Those controls were done and had been referred to in court, but Vecchiotti and Conti overlooked this, claiming there was no record of them.
...
It was the responsibility of the experts to look at all the data available, Nencini said, but Vecchiotti and Conti did not. Their report cites no proof of negative and positive controls for contamination, yet Nencini found a deposition from one of the preliminary hearings in October 2008, where Stefanoni clearly said they had been done, and, in fact, examples of such were deposited that day. He notes that one of prosecution consultants requested and obtained that data and used it to rule out contamination. The fact that the two independent experts completely overlooked this data showed a “scarce attention was being given to the case documents deposited with the court.”
But there is more, Nencini writes.
The decision not to test Trace “I” of DNA that was later revealed to be a trace of Amanda Knox’s DNA on the handle of the kitchen knife was an autonomous decision of the two experts that was communicated verbally to the consultants, but was not a joint decision of all the forensic consultants, as the experts suggested. Court records show the Kercher family and prosecution’s forensic consultants all maintained in September 2011 that the technology existed to trace the small trace and requested that it be done. That Professor Vecchiotti convicingly and repeatedly said it could not be tested was “clearly in error.” The Nencini court went ahead with the testing, and the RIS in Rome were able to get a reliable result, following all double amplification requirements and international protocols. Nencini notes that RIS officials as well as other consultants testified that the kit for identifying such a small trace of DNA was available on the Italian market back in 2011, but they were ignored. The trace should have been tested, Nencini wrote, and by reporting that it was impossible to do so, the experts contributed to an error of judgement by the presiding magistrate, whose ruling was eventually tossed. Nencini considers several pages of statistical and genetic analysis made by various consultants in both the first and second appeals. On page 221, he writes that “the behavior of Vecchiotti was “censurable” because before providing an imprecise report in a trial, she should have requested the controls documentation from the forensic police and only in the case of that data not being provided, come to the conclusions that she did.
