The Court said that although the platforms, which merely facilitate publication by others, could not be held liable for defamatory comments posted by others if they had not been informed of the existence of the material, it was possible to hold platforms liable as publishers of the material themselves if they fail to act speedily enough to remove the content once notified of its presence.
The Court was ruling in a case in which it dismissed an appeal by a former Conservative council elections candidate Payam Tamiz in which the politician claimed that Google should be held liable for allegedly defamatory comments posted about him by users of Google's 'Blogger' service.
Because only the author, editor or publisher of defamatory content can be held liable for that defamation, the Court set out to consider whether the internet giant could be said to have been a publisher of the material posted on Blogger.
The High Court had previously ruled that Google was not a publisher of the material. However, the Court of Appeal said that the High Court was wrong to dismiss the possibility that Google had assumed the role of publisher at some point after it had received notice of the allegedly defamatory comments.
"If Google allows defamatory material to remain on a Blogger blog after it has been notified of the presence of that material, it might be inferred to have associated itself with, or to have made itself responsible for, the continued presence of that material on the blog and thereby to have become a publisher of the material," Lord Justice Richards said in the ruling.
"I do not consider that [a determination on whether Google could be classed as a publisher in the case] could properly be drawn until Google had had a reasonable time within which to act to remove the defamatory comments," the judge added.
Principles derived from a judgment of the Court of Appeal in 1937 led the Court to determine that Google could be considered to have published the comments Tamiz had complained about. In the 1937 case the Court had deemed golf club proprietors to have published comments that had been pinned on the noticeboard in the clubhouse by someone else. Although the 1937 Court had ruled that the noticeboard comments held no defamatory meaning, it had considered the proprietors to have published them because they had been left on the board for a period of "some days".
"The very considerations that lead me to conclude that Google arguably became a publisher of the defamatory comments on [the 1937 case] principles also tend towards the conclusion that following notification it knew or had reason to believe that what it did caused or contributed to the continued publication of the comments," Lord Justice Richards said. "[In another case] the judge ... thought it arguable ... that at some point after notification Google knew or had reason to believe that its continued hosting of the material in question caused or contributed to the publication of a defamatory statement. In my view the same can be said in the present case."
The Court said that although Google's response in dealing with Tamiz's complaint was "somewhat dilatory", the time it took to remove the material after being notified of its existence was not "outside the bounds of a reasonable response". However, it said that that finding did not automatically mean Google could not be held liable for the allegedly defamatory comments.
The Court said that Google could only be considered a publisher for a "very short" period of time in the context of the case, but it dismissed the claims that it was liable for defaming Tamiz after determining that there had been no "real or substantial" wrongdoing against him as a result of the comments.
"The allegedly defamatory comments were posted between 28 and 30 April [in 2011], soon after the initial blog of 27 April," Lord Justice Richards said. "By the very nature of a blog, they will have been followed by numerous other comments in the chain and, whilst still accessible, will have receded into history. As I have indicated, the earliest point at which Google could have become liable in respect of the comments would be some time after notification of the complaint in respect of them. But it is highly improbable that any significant number of readers will have accessed the comments after that time and prior to removal of the entire blog."
"It follows, as the judge clearly had in mind, that any damage to [Tamiz's] reputation arising out of continued publication of the comments during that period will have been trivial; and in those circumstances the [High Court] judge was right to consider that 'the game would not be worth the candle'. I do not accept [arguments made on behalf of Tamiz] that various other features of the claim, including the fact that [Tamiz's] name is relatively uncommon and distinctive in this jurisdiction, undermined the judge's conclusion," he added.
"It follows that, despite the fact that I have reached certain conclusions favourable to [Tamiz] on the previous issues, this appeal must in my view fail," the judge said.
The Court did not consider, if it had held the opposite view, whether Google would have had a defence to being deemed liable for defamation under the terms of the UK's E-Commerce Regulations.