Italy’s top court is expected to decide whether to uphold the convictions of Amanda Knox and Raffaele Sollecito for the 2007 murder of British student Meredith Kercher.
The Court of Cassation in Rome will hear from Sollecito’s defence team before the judges give their verdict.
Former lovers Knox and Sollecito were convicted for the second time in 2014.
They have maintained their innocence throughout and have already served four years in prison.
Earlier this week, the court heard Knox’s lawyer’s arguments that her conviction was a grave judicial error.
The verdict was originally due on Wednesday but was delayed to hear Sollecito’s defence team.
The court will either confirm the guilty verdict or overturn it – by ordering another trial or effectively bringing about an acquittal.
A definitive conviction would trigger complicated attempts to extradite Knox, who currently lives in Seattle in the US.
Sollecito, from Bari, southern Italy, has remained in the country, and attended the court with his current girlfriend on Wednesday.
The Kercher family’s lawyer, Francesco Maresca, expressed hopes at the last hearing that the court’s decision would bring an end to the judicial process.
“They hope that this will be the final stage of this judicial process and they will at last… be able to remember Meredith outside of the court room [process]”, he said.
Leeds University student Meredith Kercher, 21, from Coulsdon, south London, was found dead in the flat she shared with Knox, now 27, in Perugia, central Italy, where both women were studying.
Her partially-clothed body was found under a duvet in her bedroom, which had been locked from the inside. Her throat had been cut.
Prosecutors claimed she was killed as part of a bungled sex game. Knox and Sollecito, 30, were convicted of the murder by a trial court in Perugia in 2009.
They were freed in 2011 after an appellate court overturned the convictions.
The Court of Cassation rebuked the appellate judge’s reasoning and last year an appeals court in Florence sentenced Knox to 28 years and Sollecito to 25 years.
Rudy Hermann Guede, born in the Ivory Coast, who opted for a fast-track trial, is serving a 16-year sentence for his role in the murder.
The high-profile case has inspired books and at least two films, and Kercher’s family has said Meredith, the real victim, risked being forgotten.
Originally portrayed as a fast-living partygoer, Knox came to be seen in much of her home country as a victim of a botched investigation and an unwieldy justice system.