The case, which has inspired books and films, has riveted media attention for eight years and the court’s eventual decision could trigger a legal battle over Knox’s extradition.
The Court of Cassation began the hearing yesterday and had been expected to decide later in the day but closing arguments went slowly and judges rescheduled for tomorrow morning.
Knox, 27, and Raffaele Sollecito, 30, were convicted for the second time last year for the murder of 21-year-old Kercher, an exchange student from the University of Leeds who was stabbed to death in a house the women shared in Perugia, a university city in central Italy.
A confirmation of the convictions could trigger a complicated battle to try to extradite Knox from the United States. Sollecito, whose passport has been withdrawn and who attended the hearing, could be arrested.
The court might, however, overturn the conviction, and then either order yet another trial or effectively acquit the two — though experts said that last option was unlikely.
Both Knox and Sollecito have maintained their innocence throughout.
Knox, who is now 27, was not in court to see if her 28-year sentence is confirmed.
Sollecito, 30, who has had his travel documents seized, was mobbed by the media as he made his way into the Palace of Justice in central Rome. He faces a sentence of 25 years.
The Kercher family were not in court yesterday but have said that if Knox’s conviction is confirmed they want authorities in the US to extradite her to Italy.
Kercher family lawyer Francesco Maresca said earlier this week: “The interest of the family is to arrive to the end of this trial. They want to be able to remember Meredith outside of the court room.”
Knox said last year she would become a “fugitive” if convicted and would have to be taken back “kicking and screaming” to Italy.
If her conviction is upheld she could delay going to jail if she were pregnant, according to Italian legal experts.
Last month, she announced her engagement to 27-year-old musician and school friend Colin Sutherland, who wrote to her while she was in jail.
There has also been speculation that political pressure from the US could hamper the extradition process.
Sollecito is reportedly seeking to separate his case from Knox’s, with his lawyers pointing out that a partial confession written by the American and later retracted did not mention his presence at the scene of the crime.
If that argument succeeds, the Italian could be given a new trial.
Washington has refused to send military personnel to serve sentences in Italy in the past, but sparing a private citizen from extradition would be an “anomaly”, Pier Luigi Petrillo, Professor of Comparative Law at Rome’s LUISS university, said.
“If an American citizen has been found guilty of a crime , there is an obligation by the United States to extradite the American citizen,” Petrillo said.