Amanda Knox to Be Extradited to Italy? >>Hollywood

Tuesday's ruling by Italy's Supreme Court ordering a new trial for Amanda Knox guarantees the already long-running legal saga will drag on for years.

It also raises the possibility that if Knox is found guilty and that verdict is upheld by Italy's Supreme Court, Knox could face a request to extradite her.

An extradition request would likely turn on whether being prosecuted again after being exonerated constitutes double jeopardy in the United States.

Knox and her ex Raffaele Sollecito were convicted in 2009 after a controversial trial for the murder of her British roommate Meredith Kercher in 2007.

Knox was sentenced to 26 years in prison while Sollecito got 25, but that verdict was tossed out in 2011 by an appeals court that blasted the prosecution's case.

Knox had hoped this week's Supreme Court ruling would uphold her innocence and put an end to her six year ordeal. Instead she was "shocked" at the result.

So were many in the U.S. who didn't know you could even re-try a case after the accused was eventually cleared, an uncommon practice in America.

In any case, Amanda Knox now faces years of legal maneuvering and hearings starting when the case is expected to go back to trial early next year.

Knox, who has already spent four years in an Italian prison, does not intend to return to Italy for the proceedings, possibly putting her lawyers at a disadvantage.

She won't be able to testify on her own behalf or use Italy's right to "spontaneous declarations" in which the defendant can refute testimony on the spot.

The former exchange student's absence at the new trial could prompt the appellate court to declare her in contempt of court, but that carries no additional penalties.

Regardless, the outcome is certain to be appealed by whichever side loses.

If Knox is again convicted and the verdict is upheld by the Supreme Court, Italy would be expected to seek her extradition in order to put her back in prison.

"We've got a [extradition] treaty," said Bruce Zagaris, a D.C.-based attorney.

"The Senate has decided that Italy is a country with which we ought to have a treaty. They wouldn't have ratified if they didn't think the Italian process was fair and due process was sufficient."

"She can try to fight extradition, but it will be an uphill battle."

In the American legal world being retried for the same crime sounds like "double jeopardy," a principle in the U.S. judicial system and enshrined in the Constitution.

Effectively, it outlaws being tried twice for the same crime.

American unease with double jeopardy could give Amanda Knox a "fighting chance" to appeal any extradition in a U.S. court, according to legal experts.

In the treaty, the U.S. functionally accepts Italy's system of justice, but it could be argued that the double jeopardy clause of the Constitution was violated.

That, in turn,