Amanda Knox's odd behavior in the days after her roommate was found stabbed to death was once again a focal point of police testimony in her Italian murder trail today.
Police described a young woman who was calm when others were crying but at times slapped herself in the head, and at one point began shaking uncontrollably and sobbing.
Knox, a 21-year-old American, made her most forceful defense yet, standing in the Perugia, Italy court to accuse police of roughly interrogating her for hours and cuffing her on the head.
Knox is on trial along with her former boyfriend, Raffaele Sollecito, for the slashing death of her English roommate, Meredith Kercher. Another man, Rudy Guede, has already been convicted of taking part in the murder.
Much of the focus of today's testimony was on Knox's behavior, which has repeatedly been cited by investigators.
In previous testimony, witnesses described Knox as calm and even cold just after the crime, and found her affectionate behavior towards Sollecito "inappropriate." One detective said he was surprised to find Knox doing a cartwheel in the police station.
Fabio D'Astolto, an English-speaking police officer in Perugia, told the court today that he was asked to come to the police station on Nov. 2, 2007, the day Kercher's body was found, to help question Knox.
"She seemed calm, as if nothing had happened, while everyone else was crying," said D'Astolto.
However, when D'Astolto accompanied Knox to have her fingerprints taken, he said Knox "paced up and down the hallway pretty nervously, and brought her hands to her head, hitting herself on the temples."
D'Astolto said her behavior worried him, and he offered to get her something to drink, but Knox said she was fine.
Another interpreter, Ada Colantone, described Knox's behavior two days later when she and the two Italian women who also shared the Perugia apartment were taken back to confirm that the knives found in the kitchen belonged there.
Knox "started shaking," recounted Colantone. "She was shaking so hard that the coroner went over to her. She was visibly upset, and made to lie down on the couch." She said Knox also began crying.
In the days following the murder, Knox, Sollecito and other people who knew the victim were called repeatedly to the Perugia police station for questioning.
On the evening of Nov. 5, three days after Kercher's body was discovered, Sollecito was called in for questioning again and, as usually happened, according to investigators, Knox also came. She was questioned as well.
Anna Donnino, an interpreter for the Perugia police, said she was summoned to the police station to translate just after midnight.
Knox was calm as police talked to her again about what she had been doing the evening of Nov. 1, the night Kercher was slain, Donnino said.
But Knox had an "emotional shock" when she was shown a text message she had sent to Patrick Lumumba, her boss at the pub where she worked occasionally.
"She brought her hands to her head, and shook it," Donnino told the court.
Knox had told police that Lumumba had texted her that she didn't need to come to work that night because business was slow. She texted him back saying, "See you later."
Italian police took the phrase as evidence that Knox and Lumumba planned to meet up later, and as a possible implication in the murder.
Donnino also said that Knox kept saying, "It's him, he did it, I can feel it," referring to Lumumba.
The questioning stopped, and when Knox was asked if she wanted a lawyer, she said no, according to Donnino. Donnino repeatedly confirmed that Knox was never mistreated, and made her statements voluntarily.
Knox was arrested at the end of the night's interrogations.
In Italian courtrooms, defendants are allowed to make statements during their trial, and Knox stood today to refute the police depiction that they treated her well and that her statements were made voluntarily.
In a respectful but insistent tone, Knox said in clear Italian, "The witnesses are denying things about the interrogation. There were hours and hours that they don't talk about, during which I confirmed my story and there was an aggressive insistence on the text message to Patrick," she said.
Knox's defense has implied that the police badgered her to implicate Lumumba and that she finally gave in.
Knox has claimed in the past that she was treated roughly that night, saying the police rejected her explanations and accused her of lying.
And she added, "I am sorry, but I really was cuffed on the head."
Lumumba was arrested on the basis of Knox's statements, but was later released and all accusations against him were retracted, when no evidence of his presence was found on the scene of the crime. Lumumba is suing Knox for defamation.
Today's hearing was not only about Knox.
Police officer Daniele Moscatelli testified about the questioning of Sollecito on that same night. Moscatelli, who was present, said that Sollecito seemed "confused and nervous" during the questioning and said that police discovered that Raffaele was carrying a knife in his pocket.
Sollecito's knife was later ruled out as the possible murder weapon, but was considered important at the time. Moscatelli testified that Sollecito "said he was a fan of weapons and knives."
Moscatelli said that he removed Sollecito's shoes, in order to compare them to prints found on the crime scene, but returned them not long afterwards.
Sollecito also stood up in court to defend his version of events, telling the court that his requests to call his father or a lawyer were denied that night, and that he was left shoeless for hours, even when he was taken by investigators to his apartment for an inspection.
Sollecito was arrested early the next morning, based on what the police claimed was a match between his shoe and a print on the scene of the crime. This shoe print later turned out to belong to Guede.
The trial continues on Saturday, when the court will hear from police computer experts on what they found on inspection of the defendants' computers.
Zachary Nowak in Perugia contributed to this report.