DNA evidence in Knox case is valid, argues police expert

AN ITALIAN forensic police expert — who conducted the original investigation in the case of American college student Amanda Knox — insists there was no contamination on crucial pieces of evidence linking Knox and her co-defendant to the murder of her British roommate.

Patrizia Stefanoni examined DNA traces in the aftermath of the 2007 Meredith Kercher killing.

But her work was criticised by the court-appointed experts who have alleged glaring errors in evidence gathering and possible contamination, including on a knife considered to be the murder weapon.