Knox Appeal: The Prosecution Strikes Back

Amanda Knox entered the courtroom today for the second day in a row. This time she was wearing olive green satin blouse and black slacks, and gave a smile to her father, stepfather, and best friend as she was led to her seat. Dr. Patrizia Stefanoni (above) took the stand again today to dispute the DNA results given by the two court appointed experts, Professors Carla Vecchiotti and Stefano Conti.

Yesterday Dr. Stefanoni was armed with 119 PowerPoint slides to explain her analysis. During her presentation some had a hard time staying awake in the dimly-lit, hot courtroom; even Knox seemed to nod-off a bit. As Dr. Stefanoni took the stand, Judge Claudio Pratillo Hellmann joked about it saying, “I’m glad to see you have no slides,” he said with a wry smile. Still, Dr. Stefanoni did, however, use more slides. Under questioning by prosecutor Manuela Comodi, Dr. Stefanoni defended the methods and equipment used in the investigation.


Dr. Stefanoni told the court that the machine used for the DNA examination was clean, and she rejected suggestions that the clasp had been contaminated. Dr. Stefanoni said the knife was tested in a lab six days after investigators had analyzed a trace of Kercher’s DNA, and she insisted that contamination did not occur.

Dr. Stefanoni also insisted that during period of 46 days after the killing that it took to collect the bra clasp, “nothing from outside the victim’s room was brought inside.” She insisted that out of 133 specimens analyzed in the house of the murder—including 89 in Kercher’s room—Sollecito’s genetic profile was only found in a cigarette butt in an ashtray, mixed with Knox’s. “If Sollecito’s DNA had somehow traveled from the butt to the clasp, then there would be Knox’s DNA as well on the clasp,” she said. This is something that I have posited and discussed long ago (SEE HERE for further explanation).

Also called to the stand by the prosecution was Giuseppe Novelli, an expert on human genetics at Rome’s Tor Vergata University. Novelli said he reviewed the prosecution’s procedures and he “absolutely excludes” contamination on the knife and bra clasp. Then he made a very valid point of common sense. “If the origin and vehicle of contamination is not proved, this is just a hypothetical theory,” Novelli said, adding that experts did not state precisely how the two items may have been contaminated with DNA.

The prosecution also called Francesca Torricelli, the director of a Genetical Diagnostic Center at the University of Florence. She argued that the DNA evidence was credible, and she had looked at the data and came to the same conclusions as Dr. Stefanoni. Professor Torricelli assured the court that Meredith’s DNA was on the blade of the double DNA knife.


Vecchiotti (above w/ Conti) testified in an earlier hearing that the knife tested negative for blood and the amount of DNA said to be Kercher’s was so low that it could not be examined again with any conclusions. But Torricelli refuted this claim, saying that she had witnessed the work of Vecchiotti and Conti, and that the machinery they used during their investigation could check extremely low quantities of DNA. Meanwhile, Novelli told the court that for him, and others, it was not a question of “quantity of DNA, but rather quality” to carry out a successful examination.

Outside the courtroom, prosecutor Comodi said she considered that Stefanoni and Novelli had clearly proven the good work they had done.