# 少年法 / Juveniles Act — 第三十九条 (Supplementary Provisions, Article 39)

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- Law: 少年法 (Juveniles Act), 昭和二十三年法律第百六十八号
- English title "Juveniles Act": Ministry of Justice translation
- Kind: Act — the distinction between 法律 (Act), 政令 (Cabinet Order), 省令 (Ministerial Order) and 条例 (local ordinance) decides who may issue it and what it may say.
- Provision: 第三十九条 (Supplementary Provisions, Article 39)（罰則の適用に関する経過措置） — address `suppl-4161-152/art-39`
- Text in force since: 2026-06-24
- URL (the page that opens at this provision): https://japanlaw.org/ja/juvenile-act/suppl-4161-152/art-39
- Permanent URL (e-Gov law ID, never renamed): https://japanlaw.org/l/323AC0000000168/suppl-4161-152/art-39
- Every provision below carries its address and both URLs on the line under it.
- Japanese text: e-Gov 法令検索, Digital Agency (デジタル庁). English: as marked on each line below.

Only the Japanese as published by the government has legal effect; the text
below is a copy of it. Every English rendering below is a translation and
says which kind: the Ministry of Justice's translation, or this
site's machine translation, whose model and date the Sources list names.
They are never merged and never substituted for one another.

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### 第三十九条（罰則の適用に関する経過措置） — Transitional Measures Concerning the Application of Penal Provisions
<sup>caption: machine translation, not official</sup>
<sup>suppl-4161-152/art-39 · https://japanlaw.org/ja/juvenile-act/suppl-4161-152/art-39 · https://japanlaw.org/l/323AC0000000168/suppl-4161-152/art-39</sup>

**第一項**  この法律の施行前にした行為及びこの附則の規定によりなお従前の例によることとされる場合におけるこの法律の施行後にした行為に対する罰則の適用については、なお従前の例による。
<sup>suppl-4161-152/art-39/par-1 · https://japanlaw.org/ja/juvenile-act/suppl-4161-152/art-39/par-1 · https://japanlaw.org/l/323AC0000000168/suppl-4161-152/art-39/par-1</sup>
With regard to the application of penal provisions to acts committed before this Act comes into effect and to acts committed after this Act comes into effect in the cases where the provisions then in force continue to govern pursuant to the provisions of these Supplementary Provisions, the provisions then in force continue to govern.
<sup>machine translation, not official</sup>

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## Sources

- e-Gov 法令検索, Digital Agency (デジタル庁) — 少年法 — the text in force from 2026-06-24 (https://laws.e-gov.go.jp/law/323AC0000000168/20260624_508AC0000000046), retrieved 2026-11-02
- Japanese Law Translation Database System, Ministry of Justice (法務省) — Juveniles Act — Ministry of Justice translation (https://www.japaneselawtranslation.go.jp/en/laws/view/4827/tb), retrieved 2026-11-02
- claude-sonnet-5-5 — Machine translation, batch juvenile-act-20261102T172711-004, translated 2026-11-03
- This site's parser, version 223 — 少年法 — structure, counts, cross-references and defined terms, computed 2026-11-02