Italy's highest court has overturned the 2011 acquittal of Amanda Knox, the American student who, together with her then boyfriend, was accused of killing her roommate in Perugia in 2007. It raises the possibility that Italy will seek to extradite her from the U.S. to be re-tried. U.S. constitutional protection against double jeopardy would complicate any extradition attempt, however. Knox, now a student at the University of Washington, said it was "painful" to receive the news but said she will face the continuing legal battle "confident in the truth and with our heads held high." The original trial attracted world wide attention.