The family of Meredith Kercher, the British student killed in Perugia, Italy, just over a year ago, has asked for the forthcoming trial of Amanda Knox and Raffaele Sollecito on charges of murder and sexual assault to be held behind closed doors because of what they say is the morbid interest in the case, according to the family's Italian lawyer.

Francesco Maresca said the family feared that the trial would become a media circus. He said that if the judge did not agree to the request for the trial to be held in camera, journalists should be allowed in only "two or three at a time" in rotation, with television cameramen and photographers banned altogether.

Mr Maresca said Italian law provided for trials in cases of sexual violence to be closed to the public, at the discretion of the judge. He said that showing graphic photographs and video footage of Ms Kercher's body and the murder scene in open court could do injury to her memory.

Mr Maresca said that 280 journalists had been accredited for the pre-trial hearings, which were held in camera. This led to reporters and photographers trying to snatch pictures of the accused as they arrived and left the court, with defence lawyers and prosecutors besieged by the media outside the courtroom.

He said that if this media assault was repeated for the trial of Ms Knox and Mr Sollecito, which opens on 4 December, “it would be hell. It could create problems of public order.” He said television talk shows should be banned from discussing the case while the trial was in progress.

Both of the accused deny the charges.

Mr Maresca said the case had attracted international attention partly because Ms Knox and Ms Kercher were both “beautiful, though with two completely different characters". Then there was the mix of nationalities involved: Ms Kercher was British, Ms Knox was American, Mr Sollecito was Italian, and Rudy Guede, who was sentenced to 30 years for the murder last month in a separate "fast track" trial, was an immigrant from the Ivory Coast.

Another factor was Perugia itself, an Umbrian hilltop town of steep medieval and Renaissance alleyways, passages and flights of steps “in which people, including the main actors in this crime, move from one house to another with extreme speed".

The murder of Ms Kercher was "without doubt a perfect crime," Mr Maresca told La Stampa. It was a mistake to devise a complex explanation when the crime was in fact “much simpler, I would even say banal”.

He said he did not however believe that Ms Knox, Mr Sollecito and Mr Guede had plotted a premeditated crime. They had gone to the hillside cottage which Ms Kercher shared with Ms Knox "simply to try out an erotic game".

The unforeseen had then happened, he said: Ms Kercher had refused to take part, and was killed. He said interest in the case was “morbid", with endless discussion of sexual violence and attempted sexual acts, with the added suggestion that it had something to do with the masks and sinister atmosphere of Hallowe'en.

Mr Maresca said the murder also fascinated people because it involved “degenerate" young people who smoked cannabis all day, went to bed at four in the morning, and stayed for hours on end glued to a computer screen surfing the internet, “turning their brains to mush." The Perugia crime thus offered “a photograph of today's ruined younger generation".

The prosecution is to call 90 witnesses at the trial, some of whom have only recently come forward. Last weekend it emerged that one new witness, a man in his forties, claims to have seen Ms Kercher together with all three of her alleged killers outside the cottage two days before she was murdered.

Mr Maresca said this was the first “precise indication that the three alleged killers knew each other and were together shortly before the murder". Mr Guede and Mr Sollecito claim they had never met. Italian media quoted the witness as saying “I'm certain Rudy was there because I knew him by sight and, after I saw the pictures in the newspapers, I recognised the others too.”

The bloodstained and semi-naked body of Ms Kercher, who had been stabbed in the throat, was found in her bedroom on the morning of 2 November 2007. Another new witness is said to have testified that he saw Ms Knox in a shop near the cottage at 7.45 that morning, whereas she claims she spent the night of the murder at Mr Sollecito's flat and stayed there until 10 o'clock.

Other witnesses say they heard a woman inside the cottage screaming on the night of the murder, followed by the sound of running footsteps.

Ms Knox's family and friends have launched a website for those who wish to support her defence fund. It carries photographs of Ms Knox as a child and as a student in Seattle, her home town.

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