"It is not always the case that the motive of a serious, bloody crime is easy to read," the judge wrote, especially when not in the context of other criminal activity such as financial gain. Courts have determined motives are less relevant when the evidence is clear, he said.
Kercher was found dead in a pool of blood in the apartment she and Knox shared in the town of Perugia, on Nov. 2, 2007. Her throat had been slashed and she had been sexually assaulted. Knox and Sollecito were arrested four days later and served four years in prison before an appeals court acquitted them in 2011. Knox returned to the Seattle, where she is a student at the University of Washington.
Italy's high court later threw out that acquittal in a scathing decision and ordered a new trial, resulting in January's conviction. Both Knox and Sollecito deny any involvement in Kercher's death, and say they spent the evening at Sollecito's place getting high, having sex and watching a movie.
The courts have cast wildly different versions of events. Knox and Sollecito were convicted of murder and sexual assault in the first trial based on DNA evidence, confused alibis and Knox's false accusation against a Congolese bar owner, for which she was also convicted of slander.
Then an appeals court in Perugia dismantled the murder verdicts, criticizing the "building blocks" of the conviction, including DNA evidence deemed unreliable by new experts, and lack of motive.
That acquittal was vacated in March 2013 by Italy's highest court, which ordered a new appeals trial to examine evidence and hear testimony it said had been improperly omitted by the Perugia appeals court, and to redress what it identified as lapses in logic.
Guede, was convicted in a separate trial of sexually assaulting and stabbing Kercher. His 16-year sentence — reduced on appeal from 30 years — was upheld in 2010 by Italy's highest court, which said he had not acted alone. Guede, a drug dealer who fled Italy after the killing and was extradited from Germany, acknowledges he was in Kercher's room the night she died but denies killing her.
Paolo Santalucia in Rome contributed to this report.
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