As the second appeal in the murder trial of Amanda Knox and Raffaele Sollecito began Tuesday, Oct. 1, in Florence, Italy, prosecutors say DNA evidence will be the smoking gun to convict the former couple.
Knox is the American who, along with then-boyfriend Sollecito, was charged with the 2007 murder of British exchange student, Meredith Kercher. Knox and Sollecito were convicted of the killing in 2009.
The case made international headlines and became an even bigger story as the convictions were overturned less than two years later. March 2013, the Italian Supreme Court overturned the acquittals, poising prosecutors to again hone in on DNA evidence they say was on the knife believed to be used to stab Kercher in the throat.
Police claimed the 12-inch knife, found in Sollecito's apartment, contained Meredith Kercher's DNA. According to the high court, the substance, which is not blood, was not tested properly in the first trial.
If the knife can be linked to Kercher, it could be the smoking gun, court officials said. However, the sample, at a trillionth of a gram, is trace at best. An appellate court ruled the evidence inconclusive in 2011.
Knox, now 26, is a student at the University of Washington. She is not required to attend the new trial. Sollecito told Italian media he plans to appear when the proceedings near a close.
The evidence is expected to be tested again in coming days.
Knox served almost two years of a 26-year sentence before her conviction was overturned in October 2011. Sollecito's conviction was also reversed.
Defense attorneys claim the evidence excluded the couple and has always pointed to an African drifter named Rudy Guede. The first to be convicted in the case, Guede is serving a 16-year sentence for murder and sexual assault. In a letter read in court during his trial, Guede claimed his innocence and that Knox and Sollecito killed Kercher.
Prosecutors alleged the Guede, Knox and Sollecito killed the 21-year-old as part of a Satanic sex orgy. Knox maintains she was with Sollecito at his home the night of the murder.
Kercher was found Nov. 1, 2007, in a pool of blood in the apartment she shared with Knox in Perugia, Umbria.
The case took several turns including the arrest of bar owner, Patrick Lumumba, Kercher's employer. Lumumba was later released. Prosecutors allege that Knox attempted to blame Lumumba for the crime to protect Sollecito and Guede.
It was also learned that Guede, Kercher, Sollecito and Knox smoked hashish and grew cannabis in the apartment. The discovery led Knox to tell police she and Sollecito were high on hashish when they gave inaccurate statements to investigators.
The new trial is being heard by Judge Alessandro Nencini.