Amanda Knox: A tearful appeal to overturn murder conviction (video)

American student Amanda Knox made a tearful plea on Monday to be acquitted of murdering her British roommate during a brutal erotic game, saying she was paying with her life for a crime she did not commit.

"I am the same person I was four years ago," said Knox, visibly shaking and fighting to hold back tears. "I am not what they say I am," she said, seeking to rebut prosecution suggestions that she was a manipulative, sex-mad "she-devil".

"I lost a friend, in the most brutal and inexplicable way possible. My absolute faith in the police authorities was betrayed, I've had to face absolutely unfair ... and baseless accusations. I am paying with my life for things I did not commit."

The Seattle native and her Italian boyfriend at the time, Raffaele Sollecito, are fighting a 2009 verdict that found them guilty of stabbing Leeds University exchange student Meredith Kercher to death during a drug-fuelled sexual assault.

The panel of two professional and six lay judges retired to consider a verdict immediately after Knox's final plea. Their decision is expected after 8 p.m local time (2 p.m. ET in the US) Monday.

HIGH HOPES

Expectations are high among many in the United States that 24-year-old Knox will walk free from the Perugia prison where she has spent nearly four years, after a forensic review cast deep doubt on DNA evidence used to convict her and 27-year-old Sollecito.

In his own final plea Sollecito said in a halting voice: "I am a Mr Nobody but now they want Mr Nobody to spend the rest of his life in jail."

Francesco Maresca, a lawyer for the Kercher family, did not comment on the pleas made by Knox and Sollecito, but said the Kerchers were stunned at the media clamour for their release.

"We're just hours away from a sentence in such an important trial and we continue to only hear pleas for acquittal almost as if the decision is a foregone conclusion," he told reporters.

The Kerchers -- mother Arline, sister Stephanie and brother Lyele -- missed the hearing because their flight landed just as the judges retired. But they are expected in court for the verdict.

The appeal trial has gripped attention on both sides of the Atlantic, four years after 21-year-old Kercher's body was found in a pool of blood in the university town.

The people of Perugia resent the media attention, believing the hitherto quaint image of their city has been sullied by allegations of drugs, drink and orgies among students there.

Knox, who has visibly lost weight in jail and who almost broke down at the start of her plea, told the court: "Four years ago I did not know what tragedy was. It was something I saw on TV. It was not part of me.

"I do not have contempt for life. I did not do the things they say I did. I did not kill, rape or steal."

She raised her voice to say through tears: "I insist on the truth, I insist after four desperate years on our innocence ... I want to go home. I want to go back to my life. I do not want to be punished. I do not want to be deprived of my life for something I did not do, because I am innocent."

Knox barely spoke Italian when she was arrested but addressed the court fluently, having learned the language in jail.

One of Knox's lawyers said over the weekend she was worried, but trying to keep positive ahead of the verdict.

"She is confident, she is jittery, she is waiting and a little bit frightened by the wait," lawyer Maria Del Grosso told reporters after visiting her in prison. She said Knox attended mass in prison on Saturday.

Kercher, from Coulsdon, Surrey, was on a year-long exchange programme in Perugia when she was murdered. Her body was found with more than 40 wounds and her throat had been slashed.

Knox and Sollecito were arrested days after the murder, but have steadfastly maintained their innocence throughout. A third man, Ivorian drug dealer Rudy Guede, was imprisoned for his role in the murder.

Prosecutors say Kercher was pinned down and stabbed to death when she resisted attempts by the three to involve her in an orgy. They say Knox was a cold-blooded, sex-obsessed girl who led her boyfriend astray.

They have also pointed to a fraught relationship between the two women, saying the British exchange student resented her American roommate's promiscuity.

But the prosecution's case was weakened by a review by forensic experts that undermined police scientific evidence saying traces of DNA belonging to Knox were found on a kitchen knife identified as the murder weapon. They also said alleged traces of Sollecito's DNA on the Briton's bra clasp may have been contaminated.

The defence has argued that no clear motive or evidence linking the defendants to the crime has emerged, and say Knox is innocent, falsely implicated in the murder by prosecutors determined to convict her regardless of the evidence.

The prosecution says plenty of other evidence links Knox to the crime, including her false accusation against a Congolese barman and a theft she and Sollecito are alleged to have staged in the apartment to throw police off track.

Sollecito's lawyer, Giulia Bongiorno, said her client was very emotional but strengthened by hopes of freedom. During his plea he held up a cream-coloured plastic bracelet inscribed "Free Amanda and Raffaele".

"We think that there were some big errors in the first phases of the trial but in this phase there has been more attention from the court on the key evidence," Bongiorno said. (Additional reporting by Philip Pullella and Catherine Hornby; Editing by Louise Ireland and Barry Moody)