BabyBarista, Alpha Mummy - the proliferation of weblogs on this and other news websites recently has given publishers another potential defamation headache. And they are more vulnerable to a claim than many realise.

Blogs come in all shapes and sizes, ranging from personal diaries to political analysis by professional journalists, enabling their authors to communicate their thoughts spontaneously and easily. But the immediacy and informality that makes blogs so attractive also makes them risky from a libel perspective.

Generally, journalists and authors take a great deal of care in the articles they prepare for newspapers or news websites. Their work is checked over by an editorial team, and then, if there are any legal doubts, run past an inhouse media lawyer before publication. In contrast, bloggers typically work alone, writing as fast as they think. A posting is seldom checked before it goes online. Yet bloggers are subject to the same English libel laws: the burden of proof, if a claim is brought, is on the blogger to prove what he has written is true. If he can't justify his allegations, he could be in trouble.

Bloggers have developed a reputation for addressing controversial topics head-on with a frankness that the traditional press can rarely match. But it is a myth that they can get away with more controversial content than "normal" journalists. The truth is, they are in no better a legal position than journalists, publishers and broadcasters of the old-fashioned variety. It may be true that some bloggers get away with not being sued because they have no money, but libel cases are rarely about money. They are about vindication. If an impecunious blogger was successfully sued, they could be destroyed financially.

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No only are individual bloggers at risk but, under English law, so is any other person involved in the dissemination of the blog to a public audience. Website publishers are liable for content posted to their site whether by a blogger they commissioned or an unknown third party leaving a comment on a message board or at the end of a story.

There is some leeway in the case of the latter: the law does offer an "innocent dissemination" defence. Provided the defamatory statement was not written, edited or published by one of the website's employees or contributors, the website's owners took care in relation to its publication and generally did not know about it, they may not be liable. In practice, that means a website could escape liability if it immediately removes the offending third party content as soon as it receives notice of a libel complaint.

By contrast, a website owner who commissions a blog is usually the publisher of the blog and cannot rely on innocent dissemination. If it does not provide sufficient pre-publication checks on what its bloggers are posting, it could get in serious trouble if there is a claim about the content.

This could extend even as far as private blogs maintained by its own journalists. If a reporter for The Times writes an article that is published on Times Online and then, unknown to the company, provides a follow up to the article or comments on the same subject on their own seperate weblog, readers may believe the private blog is endorsed by the company. The employee may even want readers to believe that in order to add credibility to the blog. If this occurs in the course of the employee's employment contact, The Times could be vicariously liable for the content of the journalist's private blog.

Blogs and message boards are flourishing, and every online publisher wants them. To a media lawyer, it smells like a herd of libel actions fast approaching.

The authors are media lawyers at the law firm Taylor Wessing

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