TL;DR (Updated May 2026)
- Schools owe a legally enforceable duty of care under Japan's Bullying Prevention Act (いじめ防止対策推進法, 2013). Failure to act on known bullying triggers damages liability against the school's operator (national/local government or school corporation) under the State Redress Act Art. 1 (public schools) or Civil Code Art. 715 (private schools).
- Cyberbullying is explicitly covered. Act Art. 2(1) includes "acts conducted through the internet" within the statutory definition of "bullying."
- Two parallel tracks against the bully: (1) criminal — defamation (Penal Code Art. 230, up to 3 years imprisonment or ¥500,000 fine), insult (Art. 231, strengthened in 2022 to up to 1 year or ¥300,000), intimidation (Art. 222), coercion (Art. 223); (2) civil — tort damages (Civil Code Art. 709), plus parental supervisory liability for minor bullies (Art. 714, applied up to roughly age 12).
- Anonymous online bullies CAN be unmasked. The 2022 amendment to the Provider Liability Limitation Act (改正プロバイダ責任制限法, in force October 2022) introduced a one-step court procedure ("発信者情報開示命令") consolidating what previously required two separate lawsuits.
- "Serious incidents" (重大事態, Act Art. 28) — including bullying-related suicide, hospitalization, or extended absence — trigger a mandatory investigation by the school and a report to the Board of Education / MEXT. Parents have the right to demand this investigation.
- Statute of limitations: civil damages claim is 3 years from when the victim/parent knew the harm and the perpetrator (Civil Code Art. 724); for personal injury, extended to 5 years (Art. 724-2). Criminal defamation/insult complaints must generally be filed within 6 months of identifying the offender (Code of Criminal Procedure Art. 235).
Quick Reference: Who Is Liable, and For What?
| Conduct (Online) | Criminal Liability | Civil Liability | School's Statutory Duty |
|---|---|---|---|
| Posting false rumors on SNS (LINE, X, Instagram) | Defamation, Penal Code Art. 230 | Tort, Civil Code Art. 709; parental Art. 714 | Investigate & respond, Act Art. 23 |
| Insulting messages / name-calling in group chats | Insult, Art. 231 (2022 strengthened) | Tort, Art. 709 | Same as above |
| Threatening DMs ("we will hurt you") | Intimidation, Art. 222 | Tort, Art. 709 | Report to police if severe (Act Art. 23(6)) |
| Coercing victim to do humiliating acts on camera | Coercion, Art. 223 | Tort, Art. 709 | Serious incident, Act Art. 28 |
| Sharing intimate images of a minor | Child Pornography Act Art. 7 | Tort, Art. 709 + Revenge Porn Act | Mandatory police report |
| Doxxing (address/phone/school name) | Possible Art. 230, privacy tort | Tort + invasion of privacy (constitutional Art. 13 derivative right) | Investigate, Art. 23 |
| School ignoring known bullying | — | State Redress Act Art. 1 (public) / Civil Code Art. 715 (private) | Breach of Bullying Prevention Act |
| Platform refusing to delete clearly unlawful post | — | Provider Liability Act Art. 3(1) proviso | — |
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Try for free →Statutory Framework
Cyberbullying falls under Japan's Bullying Prevention Act Art. 2(1), explicitly including internet-based bullying. Bully's criminal liability: defamation (Penal Code Art. 230, 3 years), insult (Art. 231, strengthened 2022 to 1 year), intimidation (Art. 222). Civil: tort damages (Art. 709), parental liability for minors (Art. 714). Schools must: establish prevention plans (Act Art. 13), create anti-bullying committees (Art. 22), conduct surveys (Art. 16), respond to reports (Art. 23), and investigate "serious incidents" (Art. 28). Platforms: sender disclosure (Provider Liability Act Art. 5), deletion requests (Art. 3). Resources: Children's Human Rights Hotline (0120-007-110).
Real-World Case Studies
Case 1: SNS Group Chat Bullying Leading to Suicide (Junior High School)
A second-year junior high student became the target of a closed LINE group chat created specifically to mock her. Over four months, dozens of classmates posted altered photos, fake confessions, and threats. The homeroom teacher was alerted by the parents twice and noted concerns in the school's "bullying check survey" but did not convene the anti-bullying committee required under Bullying Prevention Act Art. 22. The student took her life.
Legal outcome (typical pattern of recent decisions): The municipal Board of Education's "serious incident" investigation under Act Art. 28 found systemic failure. The bereaved parents sued the city under the State Redress Act Art. 1 and individual classmates' parents under Civil Code Arts. 709 and 714. Courts in comparable recent cases have awarded combined damages in the range of ¥30M–¥90M. Lessons: written records of parental complaints are decisive evidence; the school's failure to convene the statutory committee is itself a breach.
Case 2: Teacher Concealment Discovered Through Public Records Request
A high school student transferred out after months of online harassment. Two years later, the family filed an information disclosure request and obtained internal school records showing teachers had discussed the bullying in faculty meetings but classified it as "interpersonal friction" to avoid triggering Art. 28 reporting obligation.
Legal significance: Concealment compounds the breach. Courts have treated deliberate misclassification of bullying as an aggravating factor in damages calculations. Action for parents: every meeting with the school should be documented in writing.
Case 3: Unmasking an Anonymous Overseas SNS Account
A middle-school student was targeted by an anonymous X (formerly Twitter) account posting doctored screenshots and home-address information. Under the 2022 amended Provider Liability Limitation Act, the parents' attorney filed a single consolidated disclosure order petition (発信者情報開示命令) with the Tokyo District Court, naming both X Corp. (US) and the suspected access provider. The court issued an order requiring X to preserve and disclose IP/timestamp data, and the access provider to disclose subscriber identity.
Outcome: The perpetrator turned out to be a classmate's older sibling. Civil settlement included ¥1.2M in damages, a deletion guarantee, and a non-disclosure agreement. The 2022 amendment compressed what was previously a 12–18-month two-step process into roughly 4–8 months.
Frequently Asked Questions
Q1. How far can we go in identifying an anonymous bully online?
Under the 2022 amended Provider Liability Limitation Act, you can now file a single court procedure (発信者情報開示命令) consolidating: (1) ordering the SNS platform to disclose IP/timestamp data, and (2) ordering the access provider to disclose subscriber identity. Previously required two separate civil lawsuits. The procedure works against major Japanese platforms (LINE, Yahoo!) and major overseas platforms (X, Instagram, TikTok, Google).
Q2. Will the school actually be held responsible, or do they always escape?
It is no longer accurate to say schools "always escape." Since the Bullying Prevention Act 2013 created statutory duties (Arts. 13, 16, 22, 23, 28), failure to follow prescribed procedures — particularly convening the anti-bullying committee, conducting required surveys, and triggering Art. 28 investigations — is treated as a concrete breach. Public schools sued under State Redress Act Art. 1; private schools under Civil Code Art. 715. Multiple awards exceeding ¥50M issued since 2018.
Q3. The bully is a minor. Can we still recover damages?
Yes. Civil Code Art. 712 holds that minors lacking "capacity to assume responsibility" are not personally liable, but courts have found that children around age 12 and older possess that capacity. For younger bullies, Civil Code Art. 714 imposes liability on the parents unless they prove no breach of supervisory duty — rarely successful in cyberbullying cases.
Q4. What if the bullying happens on a platform based overseas?
Overseas platforms are reachable. Major platforms (X, Meta/Instagram, Google/YouTube, TikTok) have designated representatives or Japanese subsidiaries. For platforms without a Japanese presence, options: (1) transparency portal disclosure, (2) Japanese courts + foreign recognition, (3) parallel criminal complaint enabling police-led international cooperation.
Q5. How much can we expect in damages (慰謝料相場)?
No fixed schedule. Reference ranges: defamatory posts causing reputational harm — ¥300,000 to ¥1.5M; severe cyberbullying causing PTSD or school refusal — ¥1M to ¥5M; bullying leading to suicide — ¥30M to ¥90M including future-earnings loss against school operator and bully families combined.
Q6. The school keeps saying "we'll handle it internally." Should we accept that?
You are legally entitled to demand: (1) an Art. 28 serious incident investigation if your child has suffered significant harm or has been absent ~30 days or more; (2) a written response under Art. 23; (3) escalation to the Board of Education. Recording demands in writing (email or registered mail / 内容証明郵便) is essential.
Q7. Can we file a criminal complaint as well as a civil suit?
Yes — independent tracks. Criminal complaint (告訴) for defamation or insult must be filed within 6 months of identifying the offender (CPC Art. 235). Civil claim within 3 years (5 years for personal injury) under Civil Code Arts. 724 and 724-2. Identification via the disclosure order procedure triggers the 6-month criminal clock — move quickly.
Q8. What about the bully's parents' civil liability — directly?
Two doctrines: (1) Civil Code Art. 714 — supervisory obligor liability when the minor lacks responsibility capacity (under ~12). (2) Civil Code Art. 709 (direct) — parents themselves can be liable when they knew or should have known their child was using SNS for harassment and failed to intervene.
Action Checklist for Parents (Roadmap)
Stage 1: Evidence Preservation (Day 0)
- Screenshot every post, DM, group chat message — include URL, timestamp, account handle visibly
- Save page source / HTML where possible (or notarization service like ChibiNotari)
- Record your child's verbal account in writing, dated and signed
- Keep a chronological log (date, platform, content summary, witnesses)
- Do NOT delete the bullying account from your child's followers/contacts before evidence preserved
Stage 2: School Notification (Day 1–7)
- Notify homeroom teacher in writing (email + paper letter), citing Bullying Prevention Act Art. 23
- Request written response within 14 days, specifically asking whether anti-bullying committee (Art. 22) has been convened
- If harm is serious or absence exceeds ~30 days, demand an Art. 28 serious incident investigation in writing
- Copy the Board of Education (教育委員会) if the school is unresponsive
Stage 3: Police Consultation (Day 1–14 in parallel)
- Contact Prefectural Police Cybercrime Consultation Desk (各都道府県警サイバー犯罪相談窓口)
- For severe threats or doxxing, file an immediate criminal complaint (告訴状)
- For revenge porn / intimate image sharing involving a minor, contact police immediately
Stage 4: Lawyer Consultation (Day 7–30)
- Retain a lawyer experienced in internet defamation / school liability cases
- File a Provider Liability Act disclosure order petition (発信者情報開示命令) — must move within ~3 months due to provider log retention windows
- Send platform a deletion request (送信防止措置依頼) under Provider Liability Act Art. 3
- Calculate the 3-year civil statute of limitations (5 years for personal injury)
Stage 5: Additional Resources
- Children's Human Rights Hotline (子どもの人権110番): 0120-007-110
- 24-hour Bullying Consultation Dial: 0120-0-78310
- MEXT Bullying Comprehensive Site — for serious incident investigation precedents
Important Notes
- This article is for general information, not legal advice. Cyberbullying matters involve overlapping criminal, civil, school-administrative, and platform-governance procedures with strict time limits. Consult a Japanese-qualified attorney promptly — log retention windows at access providers can be as short as 3 months.
- Last updated: May 11, 2026. Japanese bullying law continues to evolve.
- Practice areas: Internet law (online defamation, disclosure orders), family law (minor victim representation, parental liability), school liability / state redress.