Amanda Knox is to find out later if she and her former boyfriend Rafaelle Sollecito will face another trial. The American student was acquitted of the murder of 21-year-old British student Meredith Kercher in 2011.

The highest appeals court in Italy is due to rule on a prosecution application for their convictions to be reinstated.

If the court decides against them they could face a retrial in Florence. Otherwise they will be in the clear and entitled to compensation for wrongful imprisonment.

The judges will make their decision on points of law rather than the evidence.

Meanwhile the sister of Meredith Kercher has spoken of the ''unanswered questions'' surrounding the death ahead of the final appeal today.

Family hoping for answers

Stephanie Kercher said she hoped for answers as Italian Supreme Court judges decide whether Amanda Knox and her former boyfriend Raffaele Sollecito should stand trial again or confirm their appeal hearing which saw them sensationally cleared of the brutal killing.

"There are lots of questions without answers and that's why we are looking for the truth...We hope that the Supreme Court hearing will help to find some answers to what happened that night in November 2007 when our lives changed forever" she said.

Defence lawyers and experts acting for the pair revealed how evidence had been contaminated or poorly handled by forensic teams and that the conviction should be considered unsafe.

They were immediately freed with Ms. Knox returning to her home in Seattle while Mr. Sollecito went back to Bisceglie on the southern Italian coast.

Drifter Rudy Guede is serving 16 years for the murder having initially being sentenced to 30 but this was later reduced on appeal.