Why a new defence was needed
For many years Australian publishers relied on qualified privilege when reporting on matters of public concern. In practice, the statutory version of that defence in section 30 of the Defamation Act 2005 (NSW) proved difficult for the media to establish. Reformers looked to the United Kingdom, where a public interest defence had been placed in legislation, and the 2021 amendments introduced section 29A into the uniform defamation laws.
What section 29A requires
Under section 29A it is a defence if the defendant proves two things:
- the matter concerns an issue of public interest; and
- the defendant reasonably believed that publishing the matter was in the public interest.
Both limbs must be proved, and the onus is on the publisher.
The first limb is about the subject matter. Public interest is not the same as what interests the public. Gossip about a private life will rarely qualify, while matters such as the conduct of public officials, the use of public money, health and safety, and the integrity of institutions are more likely to.
The second limb is where most of the argument happens. The belief has to be genuinely held and reasonable in all the circumstances.
The factors the court may consider
Section 29A sets out a non exhaustive list of factors the court may take into account when deciding whether the belief was reasonable. They include:
- the seriousness of any defamatory imputation carried by the matter;
- the extent to which the matter distinguishes between suspicions, allegations and proven facts;
- the extent to which the matter relates to the performance of public functions or activities of the person;
- whether it was in the public interest to publish expeditiously;
- the sources of the information and the integrity of those sources;
- whether the matter contained the substance of the person's side of the story and, if not, whether a reasonable attempt was made to obtain and publish a response;
- any other steps taken to verify the information; and
- the importance of freedom of expression in discussing issues of public interest.
The court is not required to tick off each factor, and the list is not a checklist that a publisher must satisfy. But the factors give a clear picture of responsible journalism: check your sources, test the allegation, seek a response and be careful not to present suspicion as fact.
Lessons for publishers
For media organisations, editors and anyone with an online platform, the defence rewards a disciplined process before publication. A record of the steps taken to verify a story, the attempts made to contact the subject and the reasons for publishing when you did will often be the most important evidence if a claim is made later. If you cannot show those steps, the defence becomes much harder to run.
It also pays to be careful with language. Words that distinguish between an allegation and a finding, and that fairly present the other side, reduce the seriousness of the imputations and support the reasonableness of the decision to publish.
Lessons for people who are the subject of a story
If you are contacted by a journalist before publication, take it seriously. The response you give, or do not give, may later be weighed in deciding whether the publisher acted reasonably. A considered, accurate response, prepared with advice where the stakes are high, can change the shape of the story or even whether it runs.
After publication, the existence of the defence does not mean a claim is hopeless. Whether the publisher genuinely and reasonably believed publication was in the public interest is a question of fact, and the details of what was known, what was checked and what was ignored can matter a great deal.
Other defences still apply
The public interest defence sits alongside the existing defences, including justification under section 25, contextual truth under section 26, honest opinion under section 31 and qualified privilege under section 30. Any real dispute usually involves several of them, and the right strategy depends on the facts.
If you are a publisher reviewing a story, or the subject of one, you can read about my areas of practice, get in touch, or visit Mark O'Brien Legal.
General information, not legal advice. This article is general information about the law in New South Wales as at 20 October 2026. It is not legal advice and should not be relied on as such. Laws differ between states and territories and every matter depends on its facts. For advice on your situation, please contact Mark through Mark O'Brien Legal.