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American Amanda Knox and her Italian ex-boyfriend expect to learn their fate Wednesday when Italy's highest court hears their appeal of their guilty verdicts in the brutal 2007 murder of Knox's British roommate. Several outcomes are possible, including confirmation of the verdicts, a new appeals round, or even a ruling that amounts to an acquittal in the sensational case that has captivated audiences on both sides of the Atlantic.

Here is a look at the case, the possible outcomes and issues that might come into play.

THE CASE:

Meredith Kercher, a 21-year-old student from Britain, was found dead Nov. 2, 2007 in the apartment she shared with Knox in the Umbrian city of Perugia where both women were studying. Kercher's throat was slashed and she had been sexually assaulted.

Knox, now 27, and Raffaele Sollecito, who turns 31 on Thursday, were convicted of the murder by a trial court in Perugia in 2009. They were freed in 2011 after a Perugia appellate court overturned the convictions. They found themselves back in an appellate court after the Court of Cassation vacated the acquittals in 2013 in a harsh rebuke of the Perugia chief appellate judge's reasoning.

Last year, an appeals court in Florence convicted the pair, sentencing Knox to 28 ½ years and Sollecito to 25 years. The court ruled that the pair acted in concert with Rudy Hermann Guede, a drifter born in the Ivory Coast who is serving a 16-year sentence for his role in the murder.

Knox, who spent nearly four years in jail during the investigation and after her lower court conviction, remains free in the United States. She has vowed never to return willingly to Italy.

IF THE CONVICTION IS CONFIRMED:

If the high court upholds the Florence convictions, the prosecutor's office in Florence would issue an order to execute the sentences. In the case of Sollecito, who has remained in Italy, police would seek to take him into custody immediately after receiving the order. For Knox, the situation is more complicated. The prosecutor would ask the Justice Ministry to seek her extradition, and the Justice Ministry must decide whether to comply.

Italy and the United States have an extradition treaty, and there is no formal reason for the request not to be made, according to Andrea Scella, a professor of criminal law and process at the University of Udine. However, extradition retains a political element, and the government could decide not to advance a request, accepting any political consequences from the Parliament or voters, he said.

Issues like the severity of the crime and the length of the penalty influence extradition requests. Italy's request could propose having Knox serve the sentence in the United States, as an alternative.

The timing of Italy's request is uncertain, but could unfold over months or longer.

IF THE HIGH COURT ORDERS A NEW TRIAL:

The high court can throw out all or any part of the Florence appeals court guilty verdict and order yet another appeals trial — the third in this case. It is not unprecedented in Italy for a case to be sent back to for multiple appellate rounds. In fact, one case involving the 1972 murder of a police commissioner reached the Court of Cassation nine times before the verdicts were finalized, 28 years after the murder.

No appellate trial date can be set until the reasoning for the court's decision is issued, which would contain very specific directions to the new appeals court on which elements of the case needed to be re-examined. The court has 90 days to issue its reasoning.

IF THE COURT ACQUITS:

The high court can throw out the guilty verdict without ordering a new trial, which is tantamount to acquittal. Such a decision is rare, experts say, and would require the court to give a full reasoning for its decision — also within 90 days.

For Knox and Sollecito, it would be "case closed" for their criminal court proceedings. Knox would be able to travel to Europe and Italy without risk of arrest. Sollecito, whose passport has been seized, would have his freedom to travel restored.

THE ROGUE JUROR'S INTERVIEW:

One of the civilian jurors on the panel that convicted the pair in the Florence appellate case gave an interview last week to the magazine Oggi saying she believed there was not enough evidence "to justify such a severe conviction." The interview, which violates secrecy of the deliberations, appeared to confirm rumors that the guilty finding was not unanimous. However, unanimous decisions are not required and it is unlikely to be mentioned in any of the legal teams' arguments before the high court nor have any bearing on the decision.