Why Was Amanda Knox Acquitted? Lack of DNA Evidence and Motive Played A Major Role

On Friday evening, an Italian appellate court overturned a murder conviction that would have put Washington resident Amanda Knox in prison for 28½ years. Court officials relayed the decision to Knox and ex-boyfriend Raffaele Sollecito's lawyers late in the day and told both of the beleaguered defendants that they were officially free of all charges in the murder of British exchange student Meredith Kercher. While frustrated prosecutors in the case have expressed their disappointment in the acquittal, the atmosphere in Knox's Seattle neighborhood was raucously joyful — but the nearly eight-year-long case left more than a few questions out in the open: why was Knox acquitted (again) and what evidence had changed, if any?

After her initial acquittal in 2011, court prosecutors went to work undermining her lawyers' arguments and key strategies. The victim, 21-year-old Kercher (who had been stabbed up to 40 times, been sexually assaulted, and had had her throat slit) had multiple wounds that indicated several different assailants — including Knox, they alleged. The two women had fought over money prior to Kercher's murder, despite Knox's insistence that she and her roommate were friends, said the prosecution. By January 2014, court prosecutors had decided that the evidence against Knox and Sollecito was heavy enough to warrant another conviction, and the two were slapped with murder charges once more.

This time around, however, the Italian court of appeals judge declared that enough was enough and cleared the two defendants completely. And although the official reasoning from judge Gennaro Marasca isn't due out for another 90 days, there were two major, yet definitively oddball evidentiary theories against Knox that could explain why Marasca decided to throw out the charges altogether.

Lack of DNA Evidence at the Crime Scene

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Despite the prosecution's attempts at placing Knox at the scene of the vicious murder, Knox herself might have made her own case when she told reporters in a 2014 statement that the forensic evidence collected at the scene wasn't sufficient to place her in the room on the night of the alleged killing.

"In fact," Knox said, "in the prior proceeding in which I was found innocent, the court specifically concluded that the forensic evidence did not support my alleged participation in the crime and further found that the circumstantial evidence was both unreliable and contrary to a conclusion of guilt." Defense lawyers have said time and again that the evidence prosecutors had relied on in previous cases only proved that Knox had co-habitated with Kercher — and little more.

"There is not one trace of Amanda in the room of the crime," Knox's lawyer, Carlo Dalla Vedova, told the court at the time. He also called the guilty assumption of her DNA presence in the apartment "a distortion of the facts." Before handing down their acquittal on Friday, court officials seemed to agree, throwing out all forensic evidence used in prior convictions, including a bloody knife, which forensics experts proved had belonged to Knox, and therefore accounted for her DNA on the handle.

Questionable Motives

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To date, prosecutors have yet to prove a realistic motive behind Kercher's murder. According to Sollecito's defense lawyer, Giulia Bongiorno, the entirety of the murder charges for both Knox and Sollecito were "littered with errors and absolutely littered with contradictions and by an illogical motivation", reported the AP on Wednesday.

After Knox's 2014 conviction, Italian judge Alessandro Nencini handed down an explanation for the ruling, citing that Knox must have killed Kercher because she "didn't like her". There "was an argument then an elevation and progression of aggression," concluded Nencini. On Friday, it seems Judge Marasca may have taken issue with that assumption.

In a May 2014 interview, Knox insisted that she and Kercher had not been enemies, despite what the prosecution had alleged, and maintained that Kercher's death had shaken her. "I did not kill my friend. I did not wield a knife. I had no reason to," she told CNN. "In the month that we that we were living together we were becoming friends. A week before the murder occurred we went out to a classical music concert together. We had never fought."

As more details of the acquittal arise over the next few months, Judge Marasca's ruling and the Italian court's ping-pong decision-making may begin to make more sense. For now, both Knox and Sollecito can rest easy.

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