What you need to know:

• The High Court of Australia says The Sydney Morning Herald, The Australian and Sky News are the publishers of comments by members of the public on posts on their Facebook pages. As such, they are legally responsible for their content.
• The decision comes after a lengthy legal process. Dylan Voller, a former Northern Territory detainee, is suing Fairfax Media, Nationwide News and Australian News Channel for defamation over Facebook comments made in 2016 and 2017, but the case has not progressed because of the legal definition of “publisher”.
• The decision has a profound impact on all Facebook users, media owners and brands.

The High Court of Australia has found media owners are the publishers of comments by users on their Facebook posts, in a decision that could have a profound impact on how content is shared and moderated.

On Wednesday, the High Court dismissed an appeal brought by some of Australia’s biggest media outlets – including The Sydney Morning Herald and The Australian – which were arguing they were not liable for comments made by members of the public on their Facebook posts about former Northern Territory detainee Dylan Voller.

Voller is suing Fairfax Media, Nationwide News and Australian News Channel over allegedly defamatory comments made on a series of Facebook posts linking to their stories in 2016 and 2017, but the defamation case has not proceeded because of disputes about whether the outlets were considered the publishers of the comments.

Voller was featured in an episode of the ABC's Four Corners program in July 2016, shown shackled to a chair in an Alice Springs correctional centre. The episode prompted national outrage, coverage, and a Royal Commission. 

Media outlets shared links to stories about Voller's experience, which attracted comments from members of the public. 

In court, the media outlets argued they “did not make the defamatory comments available to the public, did not participate in their publication and were not in any relevant sense instrumental to their publication; they merely administered a public Facebook page on which third parties published material”. They were, they argued, more like the supplier of a computer to an author. For a person to be a publisher, they must know of the defamatory material and intend to convey it.

The High Court by majority rejected their arguments, finding that the media outlets were involved in “facilitating, encouraging and thereby assisting the posting of comments by the third-party Facebook users [that] rendered them publishers of those comments”.

Two of the Justices wrote the media owners' “attempt to portray themselves as passive and unwitting victims of Facebook’s functionality has an air of unreality. Having taken action to secure the commercial benefit of the Facebook functionality, the appellants bear the legal consequences.”

To summarise, the Justices said, each media owner intentionally took a platform provided by Facebook, created and administered a public Facebook page, and posted content on that page. The creation of the public page, posting content on that page, “encouraged and facilitated publication of comments from third parties”.

“The appellants were thereby publishers of third party comments,” they wrote.

This court case was appealing an earlier decision from the NSW Court of Appeal, which stemmed from Voller's initial defamation cases against the publishers filed in 2017. 

Reaction to the decision

Voller’s lawyers told the ABC the ruling represents an “historic step forward” for their client and “also in protecting individuals, especially those who are in a vulnerable position, from being the subject of unmitigated social media mob attacks".

They added: "This decision put responsibility where it should be; on media companies with huge resources, to monitor public comments in circumstances where they know there is a strong likelihood of an individual being defamed.”

A spokesman for Nine, which merged with Fairfax Media in 2018, said it recognised the decision and is "obviously disappointed with the outcome. "It will have ramifications for what we can post on social media in the future," he said.

"We are hopeful that Stage 2 of the Review of the Model Defamation Provisions will take account of the High Court’s decision and the consequences of that for publishers. We also note the positive steps which the likes of Facebook have taken since the Voller case first started which now allow publishers to switch off comments on stories.” 

In a statement, Michael Miller, executive chairman of News Corp Australia, said the decision meant there was "the need for urgent legislative reform".

"I call on Australia's attorneys general to address this anomaly and bring Australian law into line with comparable western democracies," he said.

Facebook confirmed it updated its comment moderation controls earlier this year, allowing publishers to control who can comment on their posts. The company also said limiting who can comment may change the organic distribution of the post and may affect its reach. 

The University of Sydney’s media law professor David Rolph said the case was about “whether the media outlets were publishers of the third party comments posted on their public Facebook page”.

“The issues of whether the comments are in fact defamatory and whether the media outlets have a defence, such as innocent dissemination, still remain to be determined,” he tweeted.

Rolph said the ruling may prompt social media managers for publishers and brands to turn off comments or implement stricter processes. 

"This decision may mean anyone who runs a social media page can theoretically be sued over disparaging comments posted by readers or random group members — even if you aren’t aware of the comment," he wrote in The Conversation. 

Marque Lawyers wrote on Twitter: "Implications: huge."

At the time, Facebook did not allow media owners to turn off comments on posts – that has now changed.

While the ruling applies to news publishers in this case, it sets a precedent for brands and businesses across Australia that have made significant investment in owned media channels, effectively becoming publishers in the process.