Japan Defamation Laws: Civil, Criminal & Defences

Defamation in Japan is both a crime and a civil wrong. The Penal Code punishes publicly alleging facts that injure another person's reputation (Article 230), while the Civil Code lets victims sue for damages (Articles 709 and 710). A 2022 reform sharply increased the penalty for the separate crime of insult.

What counts as defamation in Japan

Under Penal Code Article 230, defamation occurs when a person publicly alleges facts that injure another person's reputation, whether or not those facts are true. The key elements are a public statement (one that can reach an unspecified or large number of people), an assertion of fact, and damage to social reputation. Japanese law treats reputation as the standing a person holds in society, so the offence protects against lowered social esteem rather than hurt feelings alone. Because the statute does not require the statement to be false, a true allegation can still be defamatory unless a statutory defence applies. Statements of pure opinion that assert no underlying fact are generally analysed differently and may fall instead under the insult provision in Article 231.

Criminal defamation and its penalties

Article 230 of the Penal Code provides that a person who publicly alleges facts injuring another's reputation is punished by imprisonment for not more than 3 years or a fine of not more than 500,000 yen. Criminal defamation is, in most cases, a complaint offence, meaning prosecution generally proceeds only after the victim files a formal complaint. The separate crime of insult under Article 231 covers publicly demeaning someone without alleging specific facts. After a Penal Code amendment that took effect in 2022, the insult penalty rose from the previous maximum of penal detention of fewer than 30 days or a fine under 10,000 yen to imprisonment for up to 1 year or a fine of up to 300,000 yen, and the limitation period for prosecuting insult was extended from one year to three years.

Defences to a defamation claim

The central defence to criminal defamation is set out in Article 230-2. A defendant is not punished if the alleged facts relate to a matter of public interest, the statement was made for the purpose of advancing the public interest, and the facts are proved true. Special provisions extend this to allegations about candidates for public office and about public officials. Even where strict truth is not fully established, courts have generally held that a defendant who had reasonable grounds to believe the statement was true may avoid liability, a standard that gives some protection to journalism and public-interest reporting. In civil cases, courts apply a comparable framework, weighing the public nature of the subject, the public purpose, and the truth or reasonable belief in truth of the statement.

Watch out: Proving you believed a claim was true is not automatically enough. The statement must also concern a genuine matter of public interest and have been made to serve that interest, not merely to harm someone.

Remedies and damages

Civil defamation is pursued under the general tort provisions of the Civil Code. Article 709 obliges a person who intentionally or negligently infringes another's rights to compensate the resulting damage, and Article 710 confirms that compensation covers non-pecuniary harm, including injury to reputation. Beyond money, Article 723 allows a court, on the victim's application, to order suitable measures to restore reputation, which in practice can include a published correction or apology. Damages awards in Japanese defamation cases have traditionally been modest by international standards, though courts assess each case on the gravity of the harm, the breadth of publication, and the defendant's conduct. Criminal penalties under Articles 230 and 231 are separate from any civil award, and a single statement can give rise to both.

Limitation period

For civil claims, Civil Code Article 724 provides that the right to seek tort compensation is extinguished if not exercised within 3 years from the time the victim learns of both the damage and the identity of the person who caused it, with an outer limit of 20 years from the wrongful act. For the crime of defamation, the general limitation rules of the Code of Criminal Procedure apply, and because defamation is ordinarily a complaint offence, the victim must also file the required complaint within the statutory window after learning the offender's identity. The 2022 reform extended the limitation period for the crime of insult from one year to three years, aligning it more closely with defamation.

Online defamation

Defamatory statements posted online, including on social media and anonymous message boards, fall under the same Penal Code and Civil Code provisions as offline defamation. A practical hurdle is identifying anonymous authors. Japan's framework for provider liability allows victims to seek disclosure of an anonymous poster's identifying information from internet service providers and platforms through a court procedure, after which the victim can pursue a damages claim or criminal complaint against the individual. The 2022 strengthening of the insult penalty was driven in significant part by concern over online harassment and cyberbullying, and the same conduct online can also support a defamation charge where it involves factual allegations rather than bare abuse.

Watch out: Sharing or amplifying someone else's defamatory post can itself create liability. Reposting a factual allegation that injures reputation is treated as making the allegation public.

How to bring a claim

A civil defamation claim is filed in the appropriate Japanese district court (or summary court for smaller amounts), where the claimant seeks damages under Articles 709 and 710 and may also request a reputation-restoration order under Article 723. For the criminal route, because defamation and insult are generally complaint offences, the victim lodges a complaint with the police or prosecutors, who decide whether to pursue charges. Many disputes, especially online ones, begin with a provider-disclosure request to unmask an anonymous poster before any substantive claim is filed. Because procedures and limitation periods are strict, anyone considering action consults a qualified Japanese lawyer (bengoshi) promptly.