By Deepa Babington
PERUGIA, Italy (Reuters) - An Italian prosecutor attacked on Saturday the "embarrassing" performance of forensic experts who shed doubt on evidence used to convict American student Amanda Knox for the murder of her British housemate.
On the second day of closing arguments in Knox's appeals trial in the university town of Perugia, prosecutor Manuela Comodi questioned the methods used by the experts whose work was not up to standards, she said.
"Would you entrust the marriage of your only daughter to a cook who knew all the recipes by heart but has never cooked?" Comodi asked the panel of lay and professional judges.
The experts' report boosted Knox's case for being absolved of murdering Meredith Kercher with her Italian boyfriend Raffaele Sollecito during a frenzied sex game in 2007. The Seattle native has already spent nearly four years in prison.
Their report concluded traces of Sollecito's DNA found on Kercher's bra clasp could have been due to contamination. But if contamination had occurred, DNA belonging to many others would also have been found on the clasp, Comodi argued.
Pulling out a white bra, Comodi said Sollecito's DNA ended up on the clasp when he pulled one end of Kercher's bra strap and cut off the bra with his other hand.
Kercher's murder and Knox's trial has transfixed Italy, Britain and the United States, helped in large part by the American's fresh-faced good looks and the gruesome nature of the murder.
A verdict in the appeals trial is expected after concluding arguments from both prosecution and defense at the end of next week, nearly four years after the murder stunned Italy and shook Perugia's image as an idyllic student town in the Umbrian hills.
Knox was sentenced in 2009 to 26 years in prison and Sollecito to 25 years for the murder. Rudy Guede, an Ivorian drifter with a criminal record, is also serving time for taking part in Kercher's murder.
All three say they are innocent.
(Editing by Robert Woodward)