The parents of a US student convicted of murdering her British roommate in 2007 were ordered Tuesday to also stand trial in Italy for allegedly libeling police in Perugia, the university town where the murder took place, reported the dpa. The trial of Curt Knox and Edda Mellas is set for July 4, the ANSA news agency reported, citing the Perugia magistrate who made the decision. In a 2009 interview with Britain's Sunday Times, Knox and Mellas, said that their daughter Amanda Knox "had not been given an interpreter, had not received food and water, and had been physically and verbally abused" by police after her arrest for the murder of British exchange student Meredith Kercher, ANSA said. They also claimed that police struck Amanda and told her "things will get worse for you" if she requested an attorney. The pair deny any wrongdoing, according to statements by their lawyers cited by ANSA. Knox, 23, was sentenced in December to 26 years in prison for Kercher's death at the house the two shared in Perugia. Kercher, 21, was found in November 2007, with her throat slashed. Knox's, Italian national Raffaele Sollecito, was also found guilty of the murder and is serving a 25-year sentence. A third person, Rudy Guede, originally from the Ivory Coast, was also convicted for the murder in a separate fast-track trial. He is serving a 16-year prison sentence. Knox and Sollecito are currently appealing their convictions, with their lawyers disputing the finding of DNA traces on Kercher's bra and on a knife that prosecutors say implicated the two in the murder. Forensic experts were to begin retesting the evidence used to convict the pair later this month. They must conclude their findings and present them before a jury by May 21.