Decision nears in Italy in case of slain Briton

updated 2:37 p.m. ET Oct. 27, 2008

PERUGIA, Italy - Prosecutors rejected claims Monday that police contaminated evidence used for its case and requested an American woman and her former Italian boyfriend stand trial for killing a British student.

The prosecution closed its arguments Monday at the courthouse in Perugia, central Italy, and a judge is expected to rule Tuesday whether Amanda Knox and Raffaele Sollecito will go on trial for the killing.

Meredith Kercher, a 21-year-old student from Leeds University in England, was found dead in her bedroom Nov. 2 from a stab wound to the neck. Prosecutors say she was killed while an unwilling participant of a sex game.

They also asked that a third suspect, Rudy Hermann Guede of Ivory Coast, be sentenced to life. Guede is undergoing a fast-track trial at his request.

All suspects, who appeared in court Monday, deny wrongdoing.

Evidence allegedly on bra
Prosecutors claim that key evidence linking Sollecito to the death is from his DNA found on the victim's bra.

But Sollecito's defense argued in the closed-doors hearing that multiple DNA traces were found on the bra — not just from one person — suggesting the evidence was inadvertently contaminated by police. Lawyers said the traces were compatible with the DNA of fellow suspects Knox and Guede, as well as of other people.

"This is not a genetic trace belonging to one single person but it's a mix, a combination resulting from contamination, obviously involuntary, and therefore should not be admitted as evidence in court," one of Sollecito's lawyers, Giulia Bongiorno, said. She cited an examination by a defense team expert.

Prosecutor Manuela Comodi said during a break in the proceedings that "we gave a substantially different interpretation on the same elements" than the defense, including the bra.

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