FLORENCE,Italy - The retrial of Amanda Knox and her former lover for the murder of a British student begins in Florence on Monday, reanimating debate over who lies behind one of Italy's most notorious killings.
US student Knox and Italian Raffaele Sollecito spent four years behind bars for the murder of Meredith Kercher, who was found half-naked in a pool of blood in the house she shared with Knox in 2007, her body riddled with stab wounds.
Kercher's throat had been slit and she suffered a "slow, agonizing" death, according to the coroner's report.
An appeals court overturned their convictions in 2011 and Knox returned to Seattle, but Italy's Supreme Court in March ordered a retrial following an appeal by prosecutors against what they slammed a "superficial ruling."
Knox, 26, has decided not to return for the retrial, saying her stint in prison aged her by 40 years and she suffers from panic attacks and depression.
"I was depicted as a young, unscrupulous liar. A sex fiend, a murderess.
I'm not coming back," she told Florence's local Corriere Fiorentino daily on the eve of the hearing.
If Knox is convicted again and loses another Supreme Court appeal, experts say there is a remote chance that she could be extradited and imprisoned.
Sollecito, 29, has been living in the Dominican Republic but his family has said he will attend court later on in the trial, which could last months.
Retrial judge Alessandro Nencini will have to decide whether to order DNA evidence to be examined again from scratch and re-hear witness testimony.