A Tour of Defamation Case Law — How Far Can an Online Review Go Before It Is a Crime?

OPUS 평판관리팀 · Online Reputation & Defamation Response · Published 2026-06-24

Key takeaway: Three questions decide it: (1) Is the statement false? (2) Was there an intent to defame? (3) Does it serve the public interest? Courts have acquitted reviews grounded in real experience and written to help other consumers, even when somewhat exaggerated (Supreme Court 2012Do10392), while fabricated reviews describing transactions that never happened have been convicted. The most important point is that even "stating the truth" can be punished if the purpose was to defame (Constitutional Court 2017Hun-Ma1113, upholding truthful-statement defamation).

"I just wrote an honest review and got sued." Or the reverse: "A fake review wrecked my revenue." Both are common. So how do courts actually see reviews? Let's trace the line through real cases.

How the law looks at a review

Defamation requires (1) a state in which an unspecified or large number of people could perceive the statement (publicity), (2) an identifiable target (specificity), and (3) the assertion of a concrete fact — and Korea's Network Act adds (4) an "intent to defame." Article 70 of the Network Act punishes defamation by truthful statement with up to 3 years' imprisonment or a fine up to KRW 30 million (~$21,000), and defamation by false statement with up to 7 years or a fine up to KRW 50 million (~$36,000). Where the content is not a concrete fact but abuse or contemptuous language, the Criminal Act's insult offense applies instead (up to 1 year or a fine up to KRW 2 million, ~$1,400).

Acquitted review 1 — Postpartum care center review (Supreme Court 2012Do10392)

A mother who stayed 14 days at a postpartum care center posted nine times on pregnancy and parenting forums and her blog about hot-water boiler problems, noise between rooms, meal issues, and how the operator responded to her complaints — and was prosecuted for defamation under the Network Act. The Supreme Court held that the posts provided information and opinion serving the public interest by helping expectant mothers make reasonable choices, and that even with ancillary motives such as seeking a refund, it was hard to find an "intent to defame" the operator. The court ruled in favor of acquittal (decided Nov. 29, 2012).

Acquitted review 2 — A one-star delivery food rating

In a case where a one-star review complaining that "there were only three or four pieces of meat" was prosecuted as defamation by false statement, the court treated it as an expression of subjective dissatisfaction rather than an objective falsehood and acquitted the reviewer.

Convicted review 1 — A fake review of a transaction that never happened

A poster who wrote a review to the effect that the seller "sold a broken laptop," when no transaction had actually taken place, was fined for defamation by assertion of false facts. The decisive point was that the experience itself never existed.

Convicted review 2 — Posing as an insider

In a reported case, a former nursing assistant spread false claims about a clinic as if describing insider experience. The court found that a false review dressed up to seem credible carries outsized impact, recognized an intent to defame, and imposed a fine of KRW 4 million (~$2,900).

Punished for "telling the truth"? — Constitutional Court 2017Hun-Ma1113

On February 25, 2021, the Constitutional Court upheld, 5 to 4, the constitutionality of "defamation by truthful statement" under Article 307(1) of the Criminal Act (2017Hun-Ma1113 and 2018Hun-Ba330, consolidated). Even true statements can invade reputation and privacy and are therefore punishable, with the balance against free expression maintained by courts applying the public-interest defense in Article 310 broadly. In short, the common assumption that "it's true, so it must be fine" is dangerous.

In short — where the line falls

• Real experience + helpful to consumers (public interest) + not excessive in expression → good odds of acquittal.
• The transaction or experience itself is fabricated → very high risk of conviction.
• Not a concrete fact but abuse or personal attack → the insult offense applies.
• Even if true, purely defamatory intent or exposure of private life → can be punished.