An Italian court on Tuesday ordered the retrial of Amanda Knox, the American college student jailed for four years for killing her British roommate, Meredith Kercher, but acquitted after an appeal. Here are some questions and answers arising from the decision:

What just happened here?

The Court of Cassation, the Italian equivalent of the Supreme Court, overturned the acquittals of Knox and her former boyfriend, Raffaele Sollecito, and ordered them to stand trial again before an appeals court in Florence.

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They had been convicted in 2009 when Knox was sentenced to 26 years in prison and Sollecito got 25 years. An appeals court freed both of them when it overturned the convictions in 2011, ruling that prosecutors had provided faulty DNA evidence, no murder weapon and otherwise insufficient proof.

 

What was the basis for Tuesday's court ruling?

We don’t know yet. Italian law gives the court three months to explain its decision. In the American system, an appeals court would generally explain itself upon issuing the ruling.

Any idea what they might be thinking?

Prosecutors have filed 16 points of appeal — essentially disputes over how the law was applied at trial, not over the facts of the case. Among other points, prosecutors question the appeals court’s ruling that DNA testing was faulty and that certain witnesses were unreliable.

This sounds an awful lot like double jeopardy.

Italian law prohibits a version of double jeopardy — being tried anew for a crime for which you have already been cleared, said Praxilla Trabattoni, an Italian lawyer who was followed the case. This case is technically different.

Trabattoni said that the Supreme Court was essentially saying that "when the appeals court was evaluating whether she did it or didn’t, the appeals court did that on the basis of evidence that shouldn’t have been admitted.”

Italian law says that a judgment is not definitive until it’s cleared every degree of trial, Trabattoni said, and the Supreme Court is considered the third degree of trial, after the lower court and the appeals court. If the Supreme Court had upheld the acquittal and then prosecutors had brought a new case entirely, that would be considered double jeopardy under the Italian system, Trabattoni said.

What happens next?

After the Supreme Court issues its explanation, an appeals court in Florence gets the case. A retrial probably would not begin until late this year or early next year.

Where is Amanda Knox these days?

She is a student at the University of Washington, where she stayed up until at least about 2 a.m. Pacific time to learn her fate, one of her lawyers, Carlo Dalla Vedova, told reporters, according to The Associated Press. Now 25, she has a memoir, “Waiting to Be Heard,” coming out April 30, for which publisher HarperCollins reportedly paid her $4 million.

In a statement Tuesday, she said: “No matter what happens, my family and I will face this continuing legal battle as we always have, confident in the truth and with our heads held high in the face of wrongful accusations and unreasonable adversity.” 

Does she have to go back to Italy for the retrial?

No. And it appears unlikely that she will. Knox spent almost four years behind bars after her original arrest and conviction, before the appeals court reversed it. The retrial can go forward without Knox being present.

“It simply will proceed, it will be strenuously defended, and we fully expect she will be exonerated,” one of her lawyers, Theodore Simon, told NBC News.

What happens if the conviction is reinstated? Does she get sent back to jail in Italy?

We’re several big steps away from that, but it’s possible. First, Knox would have to be convicted by the appeals court. Then the Italian Supreme Court would have to uphold that verdict. Then Italy would have to seek Knox’s extradition from the United States.

The United States and Italy have an extradition treaty under which the U.S. would be bound to send Knox back, said Juliet Sorensen, who teaches international criminal law at the Northwestern University School of Law.

Such a decision would risk a political furor here at home. Knox has been portrayed by the American media as someone caught up in a hopelessly dysfunctional Italian legal system.

Still, if the conviction is reinstated, “I expect that Italy will make that request because it’s a serious crime,” Sorensen said. “At the end of the day, if she’s convicted of murder, I don’t foresee the Italian authorities letting it drop.”

And Meredith Kercher’s family? What do they make of this?

Kercher’s sister Stephanie, 29, told ITV News, the British partner of NBC News, that all the family ever wanted was the truth about the night of Nov. 1, 2007.

“We are never going to be happy about any outcome because we have still lost Meredith, but we obviously support the decision and hope to get answers from it,” she said.

What became of Sollecito, the boyfriend?

He released his own book last year: "Honor Bound: My Journey to Hell and Back with Amanda Knox." In it, he reportedly wrote that police slapped and stripped him during an interrogation, and that they tried to get him to save himself by turning on Knox.

These days he is 29 and studying in Verona, according to British newspaper reports.

Giulia Bongiorno, one of his lawyers, stressed that the Supreme Court ruling was not the same as a conviction.

“Unfortunately we have to continue the battle,” she told reporters, according to Reuters. “This is a sentence that says, with regards to the acquittal, that something more is needed.”

The Associated Press and Reuters contributed to this report.

Related:

Italy court: Amanda Knox to be retried for Meredith Kercher murder

Revealed: Why court cleared Amanda Knox

Report: Amanda Knox 'loves Italy' and might return

Amanda Knox was ordered to stand trial again for the murder of her roommate by Italy's top criminal court on Tuesday, but there appeared to be little the country could do to force her to return for the new hearings.

The Court of Cassation, Italy's final court of appeal, overturned the acquittals of both Knox and her then-boyfriend Raffaele Sollecito over the 2007 killing of British student Meredith Kercher.

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In a statement responding to the decision, Knox slammed prosecutors and vowed to fight on.

"It was painful to receive the news that the Italian Supreme Court decided to send my case back for revision when the prosecution's theory of my involvement in Meredith's murder has been repeatedly revealed to be completely unfounded and unfair," said Knox, who is now aged 25 and living in the Seattle area.

"I believe that any questions as to my innocence must be examined by an objective investigation and a capable prosecution," she added. "The prosecution responsible for the many discrepancies in their work must be made to answer for them, for Raffaele's sake, my sake, and most especially for the sake of Meredith's family. Our hearts go out to them."

Knox said that she and her family would “face this continuing legal battle as we always have, confident in the truth and with our heads held high in the face of wrongful accusations and unreasonable adversity."

Kercher, 21, died from knife wounds in an apartment that she shared with Knox in Perugia, Italy.

Prosecutors argued that Knox and Sollecito killed her after a drug-fueled sexual assault in a case that drew worldwide attention.

Young, attractive and with a seemingly bright future, the prosecution’s allegations suggested Knox’s outward appearance belied a secret, more sinister nature.

Knox was routinely referred to by a nickname "Foxy Knoxy" in newspapers as every detail of her life was examined.

She and Sollecito, who turned 29 on Tuesday, were prosecuted and found guilty of killing Kercher. Knox was sentenced to 26 years in prison, while Sollecito got 25, but they were acquitted after serving four years.

Small-time drug dealer Rudy Hermann Guede, who knew Knox, was convicted and given a 16-year sentence.

Meredith’s sister Stephanie Kercher, 29, told Britain's ITV News that the family welcomed the court's decision to retry Knox and Sollecito "in the sense that we hope to find the answers."

"We are never going to be happy about any outcome because we have still lost Meredith, but we obviously support the decision and hope to get answers from it," she said. "There are still so many unanswered questions, all we have ever wanted to do is do what we can for Meredith and to find out the truth of what happened that night."

"Rudy Guede's conviction was on the basis that there was more than one person there so that is something that needs to be looked into," she added.

Francesco Maresca, a lawyer representing Kercher's family, said in a statement on Monday that the acquittals were "defective" and "lacked transparency," Reuters reported.

"There was a lot of external pressure and the judge showed a will from the start to acquit," Maresca said.

Italian law cannot compel Knox to return to Italy and she could be tried in absentia.

Knox’s attorney, Theodore Simon, told TODAY that the student and her family were confident her acquittal would be upheld.

He characterized the outcome of Tuesday’s court decision as a "revision" of the case, as opposed to a retrial, saying: "Merely because they have sent it back for revision does not mean that anything else will happen other than she will be recognized as not guilty and the same thing will happen again."

“From what I understand, [Court of Cassation judges] have sent [the case] back for revision and reconsideration. They will review it. They may simply affirm that there was a ‘not guilty’ before and it should remain the same. They may seek to take some further evidence, but nothing has really changed.”

Simon said there was no reason for Knox to have to return to Italy, saying her presence was "no issue" in Tuesday’s ruling.

The Italian appellate court hearing the case could declare her in contempt of court but that carries no additional penalties.

"If the court orders another trial, if she is convicted at that trial and if the conviction is upheld by the highest court, then Italy could seek her extradition," another of Knox's lawyers, Carlo Dalla Vedova, told The Associated Press. 

Since her release from prison in 2011, Knox has resumed her studies in Seattle.

Knox's book about the case is due to be released in April. 

Reuters and The Associated Press contributed to this report. ITV News is the U.K. partner of NBC News.

Related:

Revealed: Why court cleared Amanda Knox

Report: Amanda Knox 'loves Italy' and might return

Italian judge slams Amanda Knox prosecutors

This story was originally published on Tue Mar 26, 2013 5:12 AM EDT

Amanda Knox "loves Italy" and would like to return despite having spent four years in a prison there before a murder conviction was overturned last year, her lawyer reportedly said.

The 24-year-old may go back to Italy as early as September because her parents are charged with slandering the Perugia police, according to an ABC News report, citing the Italian news service ANSA.

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Carlo Dalla Vedova, one of Knox's lawyers, told ANSA that Knox "loves Italy and likes Perugia" and would like to return to the country "as a tourist, but if necessary she will return to testify in the trials against her parents," ABC News said.

Knox's mother and father face a prison sentence if found guilty of slandering police officers in a 2009 interview with London's Sunday Times newspaper in which they alleged their daughter was physically abused and threatened while being questioned.

Knox spent four years of a 26-year sentence in a Perugia prison on charges that she killed her British roommate Meredith Kercher.

Her then-boyfriend Raffaele Sollecito was also convicted. A third person, Rudy Guede, was convicted of taking part in the murder in a separate trial.

Knox and Sollecito were cleared of the murder last year, but Knox was convicted of a separate charge of slandering her former boss by saying he was involved in the murder.

STORY: Amanda Knox hires attorney for possible book deal

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UPDATED 3 p.m. ET

The Associated Press offers more details about the appeals court ruling:

MILAN, Italy -- The Italian appeals court that overturned Amanda Knox's murder conviction in the slaying of her British roommate gave the reasons for its ruling on Thursday: the evidence that had been used by a lower court against the American and her Italian boyfriend just didn't hold up.

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Those shortcomings included no murder weapon, faulty DNA, an inaccurate time for the killing, and insufficient proof that Knox and Raffaele Sollecito were even at the location where the crime occurred. So said the Perugia appellate court in its long-awaited reasoning behind its October ruling that reversed the lower court's convictions.

British college student Meredith Kercher was found slain in a pool of blood on her bedroom floor in Perugia, Italy, on Nov. 2, 2007.

Knox and Sollecito, who had just begun dating at the time of the murder, were arrested several days later, then convicted in what prosecutors' portrayed as a drug-fueled sexual assault. They were sentenced to 26 years and 25 years, respectively, in proceedings that made headlines around the world.

On Thursday, the appellate cited among the other failed elements of the prosecutors' case DNA evidence, which was undermined during a re-examination in the appeals trial, and the failure to conclusively identify the murder weapon. The appellate court even contradicted the lower court's time of death, saying it happened at around 10:15 p.m., not after 11 p.m. The court said the "building blocks" used to construct the case had failed.

The appeals court also said there was no proof of the prosecutors' claim that Knox and Sollecito had helped a third man, who was convicted separately, of sexually assault Kercher, nor was there evidence that the pair had simulated a burglary by throwing a rock through a window to remove suspicion from themselves, as prosecutors alleged.

The appeals court said the lower court had arrived at a verdict "that was not corroborated by any objective element of evidence and in itself was not, in fact probable: the sudden choice of two young people, good and open to other people, to do evil for evil's sake, just like that, without another reason."

"It is not, therefore, sufficient that the probability of the prosecutors' hypothesis is greater than the hypothesis of the defense, not even when they are notably greater in number, but it is necessary that every explanation that differs from the prosecutors' hypothesis is, according to the criteria of reasonability, not at all plausible," the court said.

The only elements of the prosecutors case that were proven, the appeals court said, were the charge of slander against Knox, who was convicted of falsely accusing a bar owner of killing Kercher, and the fact that the Knox and Sollecito alibis did not match.

That the alibis were out of synch "is very different" from the prosecutors' claim of false alibis, the court said.

The proven elements combined, the court said, are not enough to support convictions against Knox and Sollecito.

"The only elements that are sustained don't allow the belief, even when put together, that the guilt of Amanda Knox and Raffaele Sollecito for the crime of murder ... has been proven," the court said.

After her conviction was thrown out, Knox, 24, returned immediately home to Seattle. She was credited with time served for the conviction of slander for accusing bar owner Diya "Patrick" Lumumba of carrying out the killing.

Prosecutors contended a kitchen knife found at Sollecito's house was the weapon because it matched wounds on Kercher's body and carried traces of Kercher's DNA on the blade and Knox's on the handle. However, the court-ordered review discredited the DNA evidence, saying there were glaring errors in evidence-collecting and that below-standard testing and possible contamination raised doubts over the DNA traces on the blade and on Kercher's bra clasp.

In addition, the defense cast doubt on the knife, questioning why Knox and Sollecito would return it to Sollecito's home if it had been used in the murder. They maintain the real weapon has yet to be found.

A third defendant in the case, Rudy Hermann Guede of the Ivory Coast, was convicted in a separate trial of sexually assaulting and stabbing Kercher. His 16-year prison sentence — reduced on appeal from an initial 30 years — was upheld by Italy's highest court in 2010.

The appeals court also expressed incredulity that the two would have cooperated in such a crime with Guede, with whom there is no proof of any relationship. "For example, there is no evidence of phone calls or text messages between the three," the court said.

 

Earlier story:

MILAN, Italy -- The appellate court in Italy that cleared American student Amanda Knox in the slaying of her British roommate released the reasoning behind its ruling on Thursday.

The Perugia court said faulty evidence was used to build the case linking Knox and her Italian boyfriend to the slaying of 21-year-old Meredith Kercher, whose body was found in a pool of blood on Nov. 1, 2007.

U.K.-based news website The Week reported that Judge Claudio Pratillo Hellman's 144-page report found that Kercher was killed by a "lone assassin."

The judge also suggested that Knox's alleged confession came because she "was stressed," according to The Week.

Knox, then a college student studying in Italy, and Raffaele Sollecito were convicted in 2009 of murdering Kercher in what prosecutors said was a drug-fueled sexual assault.

An Italian appeals court overturned their convictions in October after independent forensic investigators sharply criticized police scientific evidence in the original investigation, saying it was unreliable. 

Knox, 24, immediately returned home to Seattle, after four years in jail. 

Earlier this month, Reuters reported that Knox had hired a prominent Washington, D.C.-based lawyer as she considers possible book deals.

Knox retained attorney Robert Barnett "to represent her in discussions with various book publishers" and to help her family evaluate "other opportunities," spokesman David Marriott said.

Barnett has previously represented President Barack Obama, former presidents Bill Clinton and George W. Bush, singer Barbra Streisand and a host of other political and entertainment luminaries in book deals.

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