The constant challenge faced by the law is to adapt to social change. The social media present just such a problem becaus they are a twenty-first century means of gossiping, activity which includes the disclosure of private information and the making of defamatory allegations.
However, as we have all learnt recently, making serious allegations on Twitter - or Facebook, or anywhere simliar - can now have unpleasant consequences both for the subjects and perpetrators of such gossip.
The law concerning Twitter is straightforward: if you make a defamatory allegation  via a tweet then you are liable to be sued for libel.
The bigger question facing us as a society is whether the law should regulate this kind of communication. Its role is to balance the right of free speech guaranteed by Article 10 of the European Convention on Human Rights, with the Article 8 right to privacy and reputation. Which should take precedence on Twitter?
At the moment the law gives no immunity for Twitter gossip which infringes the rights of others. Anyone who has seen the interview with Lord McAlpine talking about the impact on him of being accused of being a paedophile will be left in no doubt about the effect the Twitter campaign (which eventually made its way into the commercial media) has had on him.
On that basis it looks like the right thing is for the twitterati to obey the same basic set of legal principles as the newspapers, broadcasters etc.
It is difficult to see the social value of allegations of paedophilia against innocent people doing the rounds on Twitter, sent by people with no basis to believe they are true. If the threat of legal sanction prevents this then such a modest qualification of the free speech right is surely in the greater public interest.
Jonathan Coad is a partner in the Media, Brands & Technology team at Lewis Silkin LLP. He can be contacted on 020 7074 8115 or at firstname.lastname@example.org 
This article first appeared in Spears  magazine.