Key Witness in Amanda Knox Trial Stumbles on Date He Saw Pair

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A key witness in the Italian trial of American student Amanda Knox gave conflicting statements in court on Saturday when asked to remember what he saw on the night of Nov. 1, 2007.

Knox, 23, and her former Italian boyfriend, Raffaele Sollecito, who turned 27 on Saturday, are appealing their 2009 conviction, of 26 and 25 years in prison respectively, for sexual assault and murder in the death of Knox's British roommate, Meredith Kercher.

Today's main witness, Antonio Curatolo, testified in Knox's first trial in 2009 that he had seen Knox and Sollecito in Piazza Grimana – the square above the house Knox shared with Kercher – on the night of the murder. Curatolo was the only eyewitness brought by the prosecution in the first trial that the judges deemed reliable.

But today he gave conflicting testimony, at one point saying he saw the two on Halloween night — before the murder — and at another suggesting he saw them the next night, Nov. 1.

In an effort to dismantle Curatolo's testimony, the defense of Knox and Sollecito called a number of witnesses on March 12. Disco owners and bus drivers testified that most discos were closed on the night of Nov. 1, 2007 because they had their big Halloween events on the night before. Bus drivers said buses to the discos were not running that night.

One owner of a discotheque on the outskirts of Perugia who testified on Saturday told the Appeals court that his disco was closed that night as were all the other big discos. He explained that for the past seven or eight years Halloween has been "the best night of the year" for Perugia discos and their big student crowd. Halloween has only become popular in Italy in the last decade or so.

Curatolo, who in 2007 lived outdoors in the Piazza Grimana square, where he said he lived for about seven or eight years, told the court on Saturday that he had seen Knox and Sollecito in the square On Nov. 1 talking animatedly. When asked what night it was, he said he thought it was Halloween, "because there were a lot of young people in costume." He said there were a lot of students around, and buses ready to take them to the discos. He also said he thought the date was Nov. 1. or 2., when All Souls Day is celebrated in Italy.

He then contradicted himself, by telling the prosecutor that he was sure that it was the very next day, at around 1 or 2 p.m., that he saw police cars driving by the square. He said he saw police "and people in white suits" inside and outside the cottage where Knox lived with Kercher. Kercher's body was discovered mid-day on Nov. 2.

"I am as certain of that as I am sure that I am sitting in this chair now," Curatolo told the judge.

In response to questions from assistant judge Massimo Zanetti, Curatolo confirmed he was presently in prison, on drug charges, he thought. "I haven't quite understood why yet," Curatolo said. According to press reports Curatolo is serving a sentence for dealing heroin – a charge dating back to 2003.

"I have always used drugs," Curatolo admitted matter-of-factly. At the moment he wasn't using any, he said, but confirmed that he had used heroin in 2007. "I want to clarify that heroin is not a hallucinogen, he added."

One of the prosecutors in the case, Manuela Comodi, told journalists before the hearing that she thought Curatolo was a "decisive" witness. He has been a witness in two other trials, she said, and the fact that he lives outside in a public place means he sees a lot of what happens around the area.

Knox appeared more relaxed on Saturday than she had at recent hearings. Her younger sister Deanna was in court along with her stepfather Chris Mellas and friend Madison Paxton.

Deanna Knox had not seen her sister since her conviction in December 2009.

"I got to see her yesterday alone, for the first time," Deanna Knox told ABC News. "We were very excited, jumping up and down, and we kind of held each other the whole time, for an hour, basically" she said.

Asked how she found her sister after all this time, Deanna replied "Amanda is always going to be just Amanda, but every time a court date comes around she gets nervous. I can tell that about her, even if she won't admit it."

Deanna also added, however, that her sister is "very, very hopeful" regarding her appeal.

The court in Perugia set the next hearing in the case for May 21, when court-assigned independent DNA experts will present their report regarding key DNA evidence presented in the first trial.

A third person, Rudy Guede, was convicted to 16 years in prison for his role in the crime. He was tried separately from Knox and Sollecito and has exhausted his appeals.