Murder in Perugia: Dangerous games of the Facebook generation

Locked up in separate cells in Perugia's new prison, Amanda Knox and her boyfriend Raffaele Sollecito have all the time in the world to ask themselves whether it was really wise (in Sollecito's case) to swathe himself in bandages from top to toe and pose for his Facebook site with a butcher's cleaver? Or for "Foxy Knoxy" (as she called herself) to kneel roaring with laughter at the controls of a machine gun pointed at the camera?

It was on Tuesday morning, four days after carabinieri broke down the door of Meredith Kercher's room in Perugia and found her body in a pool of blood, that the city police chief made the announcement: Miss Kercher's murder was solved; "the case is closed". After days of intense forensic work and interrogations, the three people accused of killing her had been arrested in early-morning raids.

And within hours we knew more about them than we could ever have wanted: their naff ideas about dressing up, their lousy sense of humour, Knox's laboured and inconsequential attempts at prose fiction. All the young people involved in the case, including the victim, belonged to the Facebook generation and, like millions of their age around the world, devoted countless hours to exposing their persons, their innermost urgings, their silliest poses and dodgiest acquaintances to anyone else with an internet connection and time to kill. Now they had been fingered by the law, there was no need for paparazzi to catch them in moments of indiscretion, no need to badger distraught relatives for snapshots. Their exposure was already total.

Modern technology also made the job of the police hugely easier. The Perugia police chief's dramatic announcement on Tuesday hinged on the fact that Knox, re-interviewed early that morning, had made a partial admission: contrary to her earlier account, in which she had placed herself in the flat of her boyfriend Sollecito when Meredith was killed, she now admitted she had been in the same flat as Meredith when "my friend" died; she had heard the dying screams, and just "covered my ears". A third person, the Congolese musician and bar owner Patrick Lumumba, was also at the house, she now claimed, and it was he who was in the room with Meredith and making her scream that way.

It was a shocking confession and it gave the police the break they needed. But now it appears that it only confirmed facts of which they were already confident: mobile phone records established where all three of the accused were at 8.30 on the night of 1 November, when they switched their phones off; they established that they switched them on again early the next morning; and that Knox and Sollecito had set off in one direction and Lumumba in another. Years ago a disgruntled friend of mine damned mobile phones, when they were still more or less optional for journalists, as " electronic tagging". Now it's clear that it's the literal truth. Scour the phone records and you can find out where any of us is at any time of night or day. Scour our Facebook and our MySpace sites and you can find out exactly what is going through our heads.

The course of events on the night of the murder is now broadly clear. Meredith Kercher had some ill-advised photos on her Facebook site too, some taken on Hallowe'en, the night before she died, with lips smeared with what was supposed to be blood, camping it up as a vampire, with friends pointing toy guns. But the 21-year-old Leeds University political science student from Coulsdon in Surrey was sober, studious, perhaps rather prudish. The post-mortem revealed no trace of drink or drugs in her system. On the night she died she had supper with girlfriends at their house nearby and watched a DVD of the soppy romantic movie The Notebook. Around 9pm she said she was tired and needed an early night and went home.

Police now believe Knox and Sollecito were waiting for her. Meredith's American flatmate and her boyfriend both came from wealthier, more privileged backgrounds than the Surrey girl – Knox from a wealthy home in Seattle, where her father is vice-president of Macy's department store, Sollecito from Bari, the beautiful capital of Puglia in southern Italy, where his father is a well-to-do urologist. They were more worldly than Meredith, more edgy, more self-indulgent. The first of November, All Saints' Day, is a public holiday in Italy; there were no university classes, and the couple seem to have spent the afternoon smoking dope. In the evening Knox was supposed to work at Le Chic, the city-centre bar run since August by Patrick Lumumba, but he sent her a text saying he was not opening. She replied, "See you later". They met in town and all three went on to Meredith's house in Via Pergola.

To do what precisely? To rape and kill the girl Knox called "my friend"? In the judge's report there is no suggestion that the accused had plotted to kill Meredith Kercher. With the exception of Lumumba, the protagonists in the macabre drama are little more than children; in his prison cell, Sollecito says over and over, "When can I see my father?" That night they played a game, but they were stoned; they had watched too many sleazy movies; Sollecito as usual had his sharp, nasty knife – and they were children no more.

Lumumba knew Meredith; Knox had brought her to Le Chic because she too fancied a part-time job. "She was a really nice girl," the African told a journalist before he became a suspect. "When she came into my bar for the first time she asked me for a vodka. We immediately became friends, and she was going to be a PR at my venue. She was going to hand out flyers." The police believe he made a pass at her which she rejected, but he couldn't get her out of his mind. That's why he was hanging around that evening in the house in Via Pergola, the little villa with the lovely view of woods and with marijuana plants and discarded syringes in the garden.

How did the evening proceed? Quite quickly, it seems. Meredith got home at 9.30. The others were waiting. Knox says that Lumumba and Meredith paired off and went into Meredith's bedroom and had sex while she "thinks" she was in the kitchen. Police say that's a lie: they were all in Meredith's room, perhaps even a mystery fourth person. Meredith had complained to her English friend Sophie Purton that Knox was always bringing men around, and here they were again.

Perhaps they all ended up in Meredith's cramped bedroom. But the mood was strange, volatile, unpredictable. Whatever it was, Meredith wanted nothing to do with it. At a critical juncture she must have said, or screamed, no I won't do that, stop it, leave me in peace, get out of my room: stone-cold sober, with the soppy plot of that romantic film still going round in her head. And given Dutch courage by their drugs, by their numbers, by their "desire for strong sensations" in the words of the judge, they said, no, we won't go away, we won't stop.

Knox held her friend down as Meredith writhed and struggled; it is believed Sollecito nicked her twice in the throat with the knife he always carried, to warn her to submit; and when she continued to scream and fight he slashed at her, carving a deep wound in her neck – and the blood began to gush and all of them suddenly saw that they had gone much too far.

Reading and writing about this awful event all week, we had consoled ourselves with the thought that at least Meredith Kercher died quickly, like a slaughtered lamb. But even that cold comfort has gone. The deep wound missed Meredith's carotid artery, according to the judge, and she took two hours to die.

Perugia will never be the same. It is a magnificent city, founded by the Etruscans and steadily built on since then, its ancient and unspoilt centre hoisted on the high table of an acropolis with grand views over the countryside. The silence of the cobbled, meandering, traffic-free lanes, the sense of being close to the sky and high above the plain, give it a heady atmosphere. It is a fabulous place to be a student: the Ibiza of foreign studies, as an Italian paper put it this week, with the most cosmopolitan population in the country and that Italian sense of being both safe and untrammelled – unpoliced, unmonitored, free.

What's gone now is the sense of safety. And the ones who have destroyed it are the privileged guest-residents themselves, who discovered only too late where their games were headed.

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