PERUGIA, Italy (CBS/AP) Amanda Knox, the American student accused of killing her British flatmate, took the witness stand for the first time Friday, telling the Italian court that she occasionally used drugs at the time of the 2007 slaying.
Knox also repeated her position that she spent the night of the murder, in November 2007, at the house of her co-defendant and ex-boyfriend Raffaele Sollecito in Perugia, central Italy.
"The declarations were taken against my will, so everything that I said was said in confusion and under pressure," Knox said.
"They called me a stupid liar; said I was trying to protect someone. I was not trying to protect anyone," she said. "I didn't know what to respond. They said I left Raffaele's home, which I denied, but they continued to call me `stupid liar'."
Police had repeatedly denied any misconduct during the night of the interrogation, or at any other point. Knox has claimed in the past that she was beaten.
She spoke in English, occasionally pausing to take a breath, her voice shaky at times.
Prosecutors contend that Knox, an exchange student from Seattle, and Sollecito murdered 21-year-old Meredith Kercher during what began as a sex game. They deny wrongdoing.
Sollecito has said he was at his own apartment, working at his computer. He said he does not remember if Knox spent the whole night with him or just part of it.
Kercher was found Nov. 2, 2007, in a pool of blood in the apartment she shared with Knox.
Knox smiled as she walked into the court before her testimony. She was dressed in a white shirt and white trousers and had her hair pulled into a ponytail. She was called as a witness in her own defense and in a civil case brought by a man she earlier accused of the killing.
Amanda Knox's mother visits her in a Perugia jail.
Knox has said she was not at her house the night of the murder. But in an earlier statement to police she accused Diya "Patrick" Lumumba, a Congolese man who has a pub in Perugia, of being the murderer.
Lumumba was jailed briefly in the case, but he is no longer a suspect and is seeking defamation damages from Knox.
Knox was being questioned by Lumumba's lawyer.
She said that everyone was "yelling at me" and "saying they'd put me in prison for trying to protect someone."
At one point, Lumumba's lawyer asked whether police had beaten her so that she would say that Kercher had been raped before dying. Knox replied, "Yes."
Knox and Sollecito have been jailed since shortly after the slaying.
They could face Italy's stiffest punishment, life imprisonment, if convicted of murder. The trial began in January and a verdict is expected after a summer break.
A third suspect in the case, Ivory Coast national Rudy Hermann Guede, was found guilty of murder and sexual violence and was sentenced to 30 years in prison. He was given a fast-track trial at his request, and his appeal is set to start in November. He, too, denies wrongdoing.
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