In the recent case of Chris Cairns v Lalit Modi, the High Court in England refused to dismiss a case of "defamation via Twitter", in circumstances where the "subscribed readership" was alleged by the defendant to be so small that the plaintiff was unlikely to sustain any harm.

The plaintiff, well known New Zealand cricketer Chris Cairns, maintained that he was defamed by 'tweets' authored by the defendant alleging Cairns was guilty of match fixing. The defendant, Mr Modi, held senior roles within international cricket and was considered one of the most influential men in cricket.

Modi sought to have Cairns' claim set aside for abuse of process due to its 'trivial' nature, arguing that there was "insufficient publication". Modi requested the Court hold a hearing to determine the extent to which the tweet was read in England before allowing the matter to be tried there.

An issue arose as to how to calculate the readership of a tweet. Two expert witnesses gave evidence that the number of recipients varied from 35 to 800. Justice Tugendhat held that the actual number of direct followers is only one consideration, as "republication" is likely to be substantial and other cases had succeeded where material was published to a single person. Justice Tugendhat determined that Cairns was able to continue the action.

Cairns' case highlights the perils of publishing via social media, including on "Twitter". For example, last month The Australian newspaper's editor-in-chief, Chris Mitchell, said he would sue journalism academic Julie Posetti for defamation in respect of a tweet she sent which purported to quote a journalist as telling her that Mitchell was "in the lead up to the election ... increasingly telling me what to write". Both Mitchell and the journalist deny the allegation.

While it is not easy to determine the extent of publication, the measure of damage to a defamed person is about more than just the number of people who subscribed to the publication. Republication can mean that a Twitter account with few subscribers could be read and passed on to hundreds of people. Think twice before twittering!

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