A little after 8 o'clock in the evening of 22 September 2010, Tyler Clementi, a gay student at Rutgers University in New Jersey, posted a status update on Facebook: "Jumping off the gw bridge sorry."

A few minutes later Dharun Ravi, the roommate who had watched him kiss another man via webcam and later attempted to stream another sexual encounter to his friends, sent him a text in which he said that "all his actions were good natured". He sent another, insisting he had no problem with Clementi's sexuality. But it made no odds. Clementi's things were later found on the edge of the bridge. He had jumped.

When the story first emerged, it was swiftly mythologised into a tale for our hyperconnected times: it became a commonplace that Ravi had put a sex tape of Clementi on the internet and that he had outed him. Neither claim is true. But now Ravi is on trial accused of hate crimes and other offences, all of which he denies, they will no doubt spread again. In fact, as a masterful piece in the New Yorker by Ian Parker makes clear, the truth is harder to be sure of. Ravi's behaviour was appalling. But the law is ill-suited to adjudicating simple bad behaviour and the weightier question of criminality is far less clear. At the heart of this case, as at the heart of all of the cases that haunt us, is a void.

Texts, Facebook messages and emails attest to the process that led up to Clementi's decision. But there is no record that can tell us what went through his mind before he leapt. The jury has to try to reach a verdict. For the rest of us, any such conclusions are fraught with difficulty. The dangers are visible in those myths about the sex tape and the outing: they suggest a public sphere obsessed with attributing tragedy not to people, but to things; a world that can't bear the idea of something unknowable and sad, and is instead preoccupied with explaining it, and hence explaining it away.

These days, the internet, being new, is the most fruitful repository for those explanations. If a killer rings his victim, the case is not known as a TELEPHONE MURDER; substitute the call with a Facebook message, on the other hand, and the interaction takes on a heavier burden.

The truth, of course, is the same in both instances: the medium did not do the thing. The person did the thing. I have no idea whether Tyler Clementi would have killed himself before the advent of the internet. But I know this: for as long as there have been bridges, there have been people standing at the top of them, with no sense of an escape route and no hope of help on the way.

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