MILAN, Italy (AP) -- No murder weapon. Faulty DNA. No motive. Even the time of death was wrong by nearly an hour. The Italian appeals court that cleared Amanda Knox in the killing of her roommate explained its ruling on Thursday: The evidence just didn't hold up.
In a 143-page document that criticized nearly every stage of the investigation that led to the conviction of Knox and her Italian boyfriend, Raffaele Sollecito, the appeals court said the lower court didn't even prove they were in the house when Knox's British roommate, Meredith Kercher, was killed.
Kercher was found slain in a pool of blood in the house she shared with Knox in the Italian city of Perugia.
Knox and Sollecito, who had just begun dating, 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.
The Perugia appellate court, which acquitted the two in October after reviewing the lower court's evidence and conducting new hearings of its own, criticized the "building blocks" of the conviction and the failure to identify a motive.
The guilty verdict "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," wrote presiding Judge Claudio Pratillo Hellmann.
Still, the three-judge panel stopped short of saying what actually might have happened the night of Nov. 1, 2007. "It is not up to this court to speculate about what actually took place," Hellmann wrote, "or whether one or more people carried out the crime."
A third defendant, Ivory Coast-born drifter Rudy Guede, 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 said there was no evidence that Knox and Sollecito helped Guede assault and kill Kercher, and expressed incredulity that they would have committed such a crime with a man they had little contact with. "There is no evidence of phone calls or text messages between the three," he wrote.
Hellmann also ridiculed the prosecution's efforts to demonize the 24-year-old Knox because she bought thong underwear days after the murder instead of more modest apparel, calling it "a garment in style and widely worn by young and not-so-young women."
Such a purchase, he wrote, "cannot be considered a show of an insensitive spirit or obscene inclinations."
He also defended Knox's behavior at a police station, where she did cartwheels and cuddled and kissed Sollecito while awaiting questioning.
Such displays could not be construed as evidence of guilt, he wrote, adding: "There are numerous ways ... to react to tragedy. An exchange of tenderness and even an exhibition of gymnastics can be explained by the need to find through gestures and behavior a bit of normality in a tragic situation."
The only elements of the prosecution case that were proven, the judge said, were a charge of slander against Knox, who was convicted of falsely accusing a bar owner of killing Kercher, and the fact that Knox and Sollecito's alibis did not match.
That the alibis were out of synch "is very different" from the prosecutors' claim of false alibis, he wrote.
And as for implicating Diya "Patrick" Lumumba after hours of intense police questioning, Knox did so because "she was convinced that was what the police wanted her to do: to name a guilty person," he said.
"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 judge said.
Prosecutors had contended that a kitchen knife found at Sollecito's house was the murder weapon, saying it matched wounds on Kercher's body and carried traces of Kercher's DNA on the blade and Knox's on the handle.
However, a 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.
The appellate court also contradicted the lower court's time of death, putting it nearly an hour earlier, at around 10:15 p.m. instead of after 11 p.m.
Knox returned home to Seattle immediately after her release, but prosecutors have said they plan to appeal her acquittal in Italy's Supreme Court of Cassation.