Anti-nuisance ordinance sexual offences are the body of provisions in the Tokyo “Ordinance on the Prevention of Violent and Delinquent Acts Causing Significant Public Nuisance” (Tokyo Ordinance No. 103 of 1962, commonly the “anti-nuisance ordinance”) that punish sexual misconduct such as groping, voyeurism and stalking. Enacted in 1962 and amended several times, they function as a norm that supplementarily punishes quasi-sexual conduct falling short of the elements of Penal Code offences. As the legislative model for similar ordinances in other prefectures, they form, alongside the Penal Code, one of the two main layers of Japan’s regulation of sexual offences. This entry covers the legislative background, the elements, the amendment history and the operational issues.

Legislative background

From postwar reconstruction into the high-growth era, public-nuisance conduct in urban areas rose, and tout-soliciting, stalking and lewd behaviour in entertainment districts became social problems. The Penal Code’s indecent assault and public indecency caught typical sexual offences but lacked provisions to punish directly the lighter physical contact, lewd speech and persistent following that lay short of them. Tokyo, needing to fill this gap as a matter of police administration, promulgated and enforced the ordinance on 11 October 1962. The original targets centred on gang-style intimidation, improper touting and yakuza-style hard selling, with sexual misconduct positioned as one part.

The ordinance aims at the comprehensive control of public-nuisance conduct short of Penal Code crimes, grasping conduct types transversally as causing “significant public nuisance.” The regulation of sexual misconduct was built into this “nuisance prevention” framework, separate from standalone statutes such as the Stalker Regulation Act and the Child Pornography Act, reflecting the legislative-resource constraints of the time and the administrative need to control mixed (sexual, economic, violent) harms together.

Elements

The groping provision (Article 5, paragraph 1) forbids, in public places and on public transport, lewd words or conduct that significantly shames a person or causes unease, including touching the body over or directly under clothing and directing lewd speech at someone. The statutory penalty is up to six months’ imprisonment or a fine of up to 500,000 yen (for habitual offenders, up to one year or one million yen). Where Penal Code Article 176 indecent assault requires “assault or intimidation,” the ordinance’s groping provision does not, functioning as a supplementary norm to catch cases, such as over-clothing contact in a crowded train, where it is doubtful whether the assault element is met.

The voyeurism provision (Article 5, paragraph 1, item 2) forbids photographing the underwear or body normally hidden by clothing in public places, on public transport, and in residences, baths, changing rooms and toilets. Before the 2018 amendment the scope was limited to “public places and public transport”; the amendment extended it to quasi-public spaces such as schools, workplaces and taxi interiors. With the miniaturization of cameras and the spread of smartphones, voyeurism cases rose to form a considerable share of prefectural-ordinance violations in police statistics. The 2023 enactment of the “Act on Punishment of Photographing Sexual Body Parts” as national law raised a new issue of overlap with the ordinance’s voyeurism provision.

The stalking provision (Article 5-2) forbids repeated following, lying in wait, demands to meet, telephone calls and emails directed at a specific person out of affection or resentment. This resembles the 2000 Stalker Regulation Act, but where that act takes a staged structure (“warning, prohibition order, penalty”), the ordinance functions as a direct-penalty provision. Further items forbid peeping into public toilets, baths and changing rooms, and lewd conduct in public places, supplementing conduct types falling short of public indecency.

Comparison with other prefectural ordinances

The Tokyo ordinance became the legislative model for similar ordinances in other prefectures (Osaka, Kanagawa and others). From the 1960s into the 1970s, similar ordinances following its structure were established across the country, forming a “nuisance-prevention ordinance network” that covers all of Japan as a supplementary norm to the Penal Code. The ordinances share a basic structure but differ in statutory penalties, elements and scope; for example, the penalty for habitual groping is up to one year and one million yen in Tokyo but up to two years and one million yen in Osaka, and the spatial scope of voyeurism and the conduct scope of stalking also vary. The Act on Punishment of Photographing Sexual Body Parts (passed and enforced 2023) criminalized part of voyeurism directly as national law, running parallel to the prefectural provisions and supplementing the limits of region-by-region enforcement (cross-border cases, cases where the photographing site is hard to identify).

Amendment history

After the Stalker Regulation Act took effect, the ordinance’s stalking provision was extended in 2005 to add contact via email and SNS. The 2018 amendment, passed by the Tokyo Metropolitan Assembly in March and enforced from 1 July, extended the spatial scope of voyeurism from public places and transport to quasi-public spaces such as schools, offices and taxis; added persistent SNS posting and GPS location-tracking to the stalking provision; and raised some statutory penalties. The amendment reflected changes in the form of sexual misconduct accompanying the spread of digital devices and SNS and led similar amendments in other prefectures. From 2023, with the national photographing-offence law in force, the adjustment of scope between it and the ordinance became an operational issue, with the ordinance increasingly oriented toward catching related conduct such as possession, transmission and public display.

Case law and the false-accusation debate

Ordinance groping cases have a distinctive evidentiary structure: the victim’s testimony is the main evidence, and eyewitness and objective evidence are often scarce. Whether there was bodily contact and intent in a crowded train is hard to establish beyond the statements of victim and suspect, and the difficulty of fact-finding has been pointed out repeatedly. A Supreme Court Third Petty Bench judgment of 14 April 2009 (a groping case on a packed train) called for caution in assessing the credibility of victim testimony and is widely cited as showing a restrained stance toward conviction in cases lacking corroborating evidence.

The film I Just Didn’t Do It (directed by Masayuki Suo, 2007), themed on a false groping accusation, made the possibility of producing innocent suspects under the ordinance a social issue, prompting debate over the operation of railway police, the conduct of interrogation and detention, and the allocation of the burden of proof in a crime type of high concealment. At the same time, the reality of groping victimization is said to far exceed the figures in police statistics, with many cases going unreported out of hesitation and fear of secondary harm, so an operation that satisfies both victim protection and the rights of the accused remains the central challenge.

Related terms

• Groping
• Non-consensual intercourse offence
• Forcible intercourse offence
• Expression regulation
• Sexual harassment