Defamation Act 2013 Section 4: The Public Interest Defence in Depth

The statutory text and its two-part structure

Section 4(1) of the Defamation Act 2013 provides a complete defence to a defamation claim where: (a) the statement complained of was, or formed part of, a statement on a matter of public interest; and (b) the defendant reasonably believed that publishing the statement complained of was in the public interest.

The defence has two limbs, both of which must be satisfied. The first is an objective question: was the statement on a matter of public interest? The second imports a subjective-plus-objective test: did the defendant reasonably believe that publication was in the public interest? A defendant who genuinely but unreasonably believed publication was justified cannot rely on s.4.

Section 4(2) adds a crucial judicial instruction: in determining reasonable belief, the court must make such allowances for editorial judgment as it considers appropriate. This provision recognises that journalistic decisions are made under time pressure and with imperfect information, and that the court should not apply hindsight when assessing the reasonableness of the belief at the time of publication.

Serious harm under s.1: the threshold claimants must clear first

Before s.4 is even engaged, a claimant must establish that the statement has caused or is likely to cause serious harm to their reputation. This is the s.1 threshold established by the Defamation Act 2013 and interpreted by the Supreme Court in Lachaux v Independent Print Ltd [2019] UKSC 27.

In Lachaux, the Supreme Court held that s.1 requires proof of actual or likely serious harm based on the facts. The defamatory tendency of the words alone is insufficient. Relevant factors include the extent to which the publication was read or accessed, the seriousness of the allegation, the identity of the persons to whom the statement was published, and any evidence of actual damage to the claimant's reputation. For bodies that trade for profit, s.1(2) requires proof of serious financial loss, not merely reputational damage.

The serious harm requirement means that many marginal defamation claims against investigative journalism cannot get off the ground. Where a story is published to a large audience about a matter of genuine public concern, the claimant must still establish that they personally have suffered serious harm — they cannot simply point to the defamatory words and assert damage.

From Reynolds to s.4: the historical context

The s.4 defence replaced the common law Reynolds privilege developed in Reynolds v Times Newspapers Ltd [2001] 2 AC 127. In Reynolds, the House of Lords recognised a new head of qualified privilege for responsible journalism on matters of public interest. Lord Nicholls set out a non-exhaustive list of ten factors relevant to whether the publication met the standard of responsible journalism, including: the seriousness of the allegation; the nature of the information and its source; the steps taken to verify the information; the status of the information; whether the claimant's side was sought; whether the story contained the gist of the claimant's version; the urgency of the matter; whether comment was sought from the claimant; and the tone and circumstances of publication.

Section 4 of the Defamation Act 2013 codified and simplified the Reynolds approach. The specific ten-factor test is gone, replaced by the two-part reasonable-belief test. However, s.4(4) specifically abolishes the Reynolds qualified privilege, meaning that cases decided under Reynolds are now primarily of historical and illustrative interest rather than binding authority on the s.4 test.

Nonetheless, the principles that animated Reynolds — verification, giving the subject an opportunity to respond, care with sources, proportionate tone — remain highly relevant to the s.4 reasonable-belief assessment. Courts will look at the same factors as indicators of whether the journalist's belief was objectively reasonable.

The reasonable belief assessment in practice

In assessing whether reasonable belief in the public interest was established at the time of publication, courts will typically examine the following:

• ›What steps were taken to verify the information? Were primary sources checked? Were documents examined? Were alternative explanations explored?
• ›Was the subject of the allegation given a meaningful opportunity to respond? Was a sufficient period allowed? Was the response, if given, fairly reflected in the published article?
• ›How reliable were the sources? Were they primary witnesses, documents, or hearsay from secondary sources? Were they motivated by personal grievance?
• ›Was the allegation proportionate to the evidence? Was it stated as established fact where only suspicion was warranted?
• ›Was the article's tone appropriate to the strength of the evidence?
• ›Was a legal read obtained before publication? Were legal concerns raised and, if so, how were they addressed?

Section 4(2)'s allowance for editorial judgment means that courts will not require perfection. A journalist who took reasonable steps but made an error of judgment will be treated differently from one who published recklessly without checking their sources. The key is that the steps taken must be commensurate with the seriousness of the allegation.

Interaction with s.2 Truth and s.3 Honest Opinion

Section 2 of the Defamation Act 2013 provides a defence where the imputation conveyed by the statement complained of is substantially true. This is the statutory successor to the old common law defence of justification. Where a journalist can prove the truth of the allegations, s.2 provides a complete defence and renders s.4 unnecessary.

Section 3 provides a defence of honest opinion where the statement is one of opinion (not fact), the opinion is based on fact, and an honest person could have held the opinion on the basis of facts existing at the time the statement was published. The key distinction between s.3 and s.4 is that s.3 applies to comment while s.4 applies to statements of fact (or mixed fact and comment). A statement of fact cannot be defended under s.3.

In complex investigations, publishers typically plead all three defences as alternatives: s.2 (the allegations are true); alternatively, s.3 (the comment is honest opinion on proven facts); alternatively, s.4 (even if not proven true, publication was reasonably believed to be in the public interest). The pleading strategy is a matter for legal advisers and will depend on the specific statement complained of.

The pre-publication legal read: establishing the s.4 defence

The pre-publication legal read is the primary mechanism by which a publication establishes the conditions for a s.4 defence. A thorough legal read serves two functions: it identifies legal risks before publication that can be addressed editorially; and it creates a contemporaneous record that the publication applied its mind to the legal issues and published in the reasonable belief that it was acting in the public interest.

A legally effective pre-publication read should cover: a defamation risk assessment of each factual allegation; an assessment of the evidence supporting each allegation; a review of the right-of-reply correspondence and the subject's response; a privacy and misuse of private information assessment; a data protection assessment; and a contempt of court check if any proceedings are active or anticipated. The lawyer's advice and the publication's response to that advice should be documented.

The legal read does not create a defence by itself — a legally read article that makes reckless allegations cannot shelter behind the fact of the read. But an article that was carefully prepared, legally reviewed, and published having addressed all identified risks is in a substantially stronger position to establish reasonable belief than one published without any pre-publication legal input. See the full guide to the legal read process.

What “public interest” means under s.4

The Act does not define “public interest”. Courts have drawn on the existing body of law developed under Reynolds and under the law of confidence to give the phrase its established meaning. Public interest is not the same as what the public finds interesting. Matters of public interest include the conduct of those who exercise public power, wrongdoing by institutions that serve the public, risks to public health and safety, financial misconduct affecting investors or employees, and the functioning of democratic and legal institutions.

Celebrity gossip, the private lives of individuals who have not sought public prominence, and commercial information about private companies with no impact on the public interest are generally not matters of public interest for s.4 purposes, whatever their audience appeal. The strength of the public interest in a story is directly relevant to the weight of the justification required for publication and to the degree of scrutiny applied to the steps taken to verify the allegations.

The more serious the potential harm to the subject's reputation, the stronger the public interest required to justify publication. A story that accuses a senior public official of serious criminal conduct requires a very substantial public interest justification and a high standard of verification. A story that mildly criticises a public institution's policy requires less.

Key distinctions at a glance

Related guides

Primary sources

• Defamation Act 2013 (legislation.gov.uk)
• Defamation Act 2013 s.4 — full text (legislation.gov.uk)
• Lachaux v Independent Print Ltd [2019] UKSC 27 (supremecourt.uk)
• BAILII — case law database
• Media Law and Democracy Initiative (mldi.org)
• Inforrm: International Forum for Responsible Media Blog (inforrm.org)

Frequently asked questions