Yahoo, Facebook and AOL have joined forces with online forum Mumsnet and the Internet Service Providers' Association in writing to the prime minister calling for urgent reform of UK libel laws.
The organisations argued in an open letter to David Cameron that online forums and ISPs are unfairly being asked to police and moderate the content of web sites, blogs and online discussions, and that libel laws have a "disproportionate and chilling effect on online writers, e-communities and web hosts".
In practice, this means that online content is often censored owing to the threat of libel action even if the content is not technically defamatory.
"[ISPs] usually have no access to the background or relevant facts and should not be expected to play judge and jury in determining whether a writer's material is defamatory or not," the letter stated. "This is a decision that can and should only be made by the direct parties involved."
The multiple publication rule also needs to be rewritten for the internet age as it currently regards each download as a new publication and potential source of new libel action, the letter noted.
The organisations are calling for a single publication rule with a limitation period of one year from original publication, and that any libel claimants should approach the author in the first instance rather than any " intermediaries".
There should also be a public interest defence in cases where "the material is on a matter of public interest and the author has acted in accordance with expectations of the medium or forum".
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