It is time to put Twitter in the dock

It was a disgraceful stunt and Cameron handled it rather well by not losing his temper and by warning there was a risk of a witch- hunt of gay politicians. But the damage had already been done, as is made clear by the Daily Star headline. A raft of prominent public figures who are probably innocent are now ineluctably connected with child abuse because their names are all over the internet.

Some on the twittersphere seem to think this doesn't matter because they're all Tories. But it does. Imagine if your father or mother were accused of being a child abuser. Imagine if you were yourself outed wrongly on Twitter as a paedophile. How could you prevent a prospective employer Googling your name before giving you the job? Are they going to spend hours establishing whether or not the claims are true? Of course not. They'll simply pass you over in favour of someone safer – no smoke without fire.

Immense harm has been done to the reputation of Lord McAlpine, the former Tory Treasurer, who is clearly not an abuser, as an investigation by The Guardian established. It was a Newsnight programme 10 days ago that launched the paedo-hunt when it reported that an un-named senior top Tory had been identified by a victim of child abuse in a Welsh children's home in the 1970s. Within hours, McAlpine's name was being posted on Twitter, along with a dozen other names including a former prime minister and five former Conservative cabinet ministers. By Friday, the story was being so widely circulated that the former Tory chairman was forced to issue a statement denying the allegations made against him, thus giving them even more publicity.

If ever there were a case of the stable door being closed after the horse had bolted, this was it. A digital hackpack, including prominent journalists such as Guardian columnist George Monbiot, had been punting McAlpine's name across the twittersphere for fully 10 days. Monbiot has since apologised for "contributing to the febrile atmosphere". But numerous blogs and websites have also published the full list of names of the alleged members of the Tory paedophile ring, including the-alternative.co.uk and Men Will Pause, a blog written by a woman called Caroline Wilde.

Now, some might be puzzled by my use of the word "published" in connection with Twitter. Most people don't think of the micro-blogging site as a publication with any editorial responsibility for what is posted there. I keep hearing references to "rumours on the internet", as if these were private conversations between individuals. Many appear to believe that, as Lord Leveson put it, Twitter is "just like people talking in a pub". If so, it is a very big pub that is visited by hundreds of thousands of people on a daily basis – far more than read any newspaper.

The truth is that Twitter is a medium of publication just like this newspaper. Consider: you can read this article online and you may be doing so now. If I were to place a link here to the tweets and websites publishing the list of "paedophile" names, you could see them in an instant. What is the difference, then, between the internet version of this article and the articles I link to? There is none. They are both in the public domain; they are mediums for the dissemination of information and views to the general public.

Under the law, newspapers are liable for any defamatory statements made by their journalists or contributors. If someone had posted Lord McAlpine's name in a comment on a newspaper website last week, the publication could have been taken to court. This is how the law on defamation works – but for some reason the law does not apply to Twitter.

Some claim Twitter is not a publisher because it doesn't edit the posts. That's irrelevant – it would be no defence against a defamatory post on a newspaper comment site that it had not been edited. Anyway, Twitter does edit its posts, and blocks anything that involves child pornography or promotes Nazi or racist propaganda. It announced last year that it also selectively blocks tweets that might be considered illegal or offensive in countries such as China or Thailand. The micro-blogging site was accused of conniving with censorship in repressive regimes. So, it cannot claim that it takes no interest in the content of tweets – it makes a lot of money from them for a start.

Now, I am utterly opposed to all forms of censorship. However, it cannot be right for blameless individuals to have their reputations destroyed by false allegations about child abuse. Being defamed on the internet is worse than being defamed by a newspaper because in the old days at least the remaining editions could be pulped. An allegation made on the internet cannot be destroyed or withdrawn. Once it's out there, it's out there. There is no way Lord McAlpine's name could be erased from the countless tweets, emails, blogs and sites where he has been falsely linked to child abuse.

And it is not going to end here. In the wake of the Savile abuse scandal, there is something like a witch-hunt going on throughout the internet. Victims are being invited to come forward with claims, often decades old, against figures of authority. More names will be posted on sites. We are told that this is unfortunate but necessary if the guilty are to be brought to justice and the victims to achieve closure. Certainly, the law should not be used to protect the rich and powerful from their wrong-doing. But the presumption of innocence has to be the basis of any fair legal system. This means protecting people from false accusations. And the only way to do this is to hold the publications themselves responsible for material appearing on their pages.

Individuals who post online are not themselves above the law, as nine men and women who recently tweeted the name of a rape victim discovered when they landed in court. A trainee accountant, Paul Chambers, was convicted in 2010 of sending a menacing communication when he joked on Twitter about blowing up an airport. Last year, a juror in a trial in Luton Crown Court, Theodora Dallas, was prosecuted just for looking up one of the defendants on the internet. It cannot be right for individuals to be brought to book but not the people who make money out of their defamations.

There is no need for new legislation or regulation of the press, only for the existing law to be enforced. There should be equal treatment of newspapers and the internet. You can't have one law for the analogue media and another for the digital media – the distinction simply cannot sensibly be made. It is time to put Twitter in the dock.