Italy's highest court of appeals was set to rule Monday whether US student Amanda Knox, acquitted in 2011 of murdering her British housemate in the university town of Perugia, will face another trial.
The court was due to rule on a 2012 prosecution appeal to reinstate the convictions against Knox and her former boyfriend Raffaele Sollecito.
Knox and Sollecito had initially been sentenced to 26 and 25 years in prison for killing and sexually assaulting Meredith Kercher in 2007, but were acquitted on appeal after four years in prison.
On filing the application last year, Perugia prosecutor Giovanni Galati said he was "convinced" that Knox and Sollecito were behind the gruesome killing.
Galati said the acquittal, which was based mainly on the admissibility of DNA evidence in the case, contained "omissions and many mistakes."
The judges will base their ruling on points of law rather than a re-examination of the evidence and the former lovers are not expected in court.
Knox "is a bit anxious and waiting for the decision, which she knows is important," Luciano Ghirga, the American's lawyer, told the Ansa news agency last week.
Should the prosecution's request be upheld, Knox and Sollecito could face a re-trial in Florence, though Knox would likely be tried in absentia.
The Seattle student returned to her home town immediately after her acquittal and the United States does not normally extradite its citizens abroad to face legal action.
Kercher, 21, was found half-naked with her throat slashed in a pool of blood in her bedroom in the house that she shared with Knox on November 2, 2007.
A third person, a local Ivory Coast-born drifter named Rudy Guede, who like the other two has always denied the murder, is the only person still in prison for the crime which prosecutors described as a frenzied sex attack.
The appeals judge who freed Knox and Sollecito in 2011 said the killing remained "unsolved" because investigators insist it must have been carried out by more than one person.