# 少年法 / Juveniles Act — 第一条 (Supplementary Provisions, Article 1)

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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: 第一条 (Supplementary Provisions, Article 1)（施行期日） — address `suppl-4161-153/art-1`
- Text in force since: 2026-06-24
- URL (the page that opens at this provision): https://japanlaw.org/ja/juvenile-act/suppl-4161-153/art-1
- Permanent URL (e-Gov law ID, never renamed): https://japanlaw.org/l/323AC0000000168/suppl-4161-153/art-1
- 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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### 第一条（施行期日） — Effective Date
<sup>caption: machine translation, not official</sup>
<sup>suppl-4161-153/art-1 · https://japanlaw.org/ja/juvenile-act/suppl-4161-153/art-1 · https://japanlaw.org/l/323AC0000000168/suppl-4161-153/art-1</sup>

**第一項**  この法律は、平成十七年一月一日から施行する。ただし、次の各号に掲げる規定は、当該各号に定める日から施行する。
<sup>suppl-4161-153/art-1/par-1 · https://japanlaw.org/ja/juvenile-act/suppl-4161-153/art-1/par-1 · https://japanlaw.org/l/323AC0000000168/suppl-4161-153/art-1/par-1</sup>
This Act comes into effect on January 1, 2005; provided, however, that the provisions set forth in the following items come into effect as of the dates specified respectively in those items.
<sup>machine translation, not official</sup>

  **一及び二**  略
  <sup>suppl-4161-153/art-1/par-1/item-1-to-2 · https://japanlaw.org/ja/juvenile-act/suppl-4161-153/art-1/par-1/item-1-to-2 · https://japanlaw.org/l/323AC0000000168/suppl-4161-153/art-1/par-1/item-1-to-2</sup>
  Omitted
  <sup>machine translation, not official</sup>

  **三**  第二条（次号に掲げる改正規定を除く。）並びに附則第三条、第四条、第六条及び第十条（次号に掲げる改正規定を除く。）の規定　平成十七年四月一日
  <sup>suppl-4161-153/art-1/par-1/item-3 · https://japanlaw.org/ja/juvenile-act/suppl-4161-153/art-1/par-1/item-3 · https://japanlaw.org/l/323AC0000000168/suppl-4161-153/art-1/par-1/item-3</sup>
  the provisions of Article 2 (excluding the amending provisions listed in the following item) and Articles 3, 4, 6, and 10 of the Supplementary Provisions (excluding the amending provisions listed in the following item): April 1, 2005.
  <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-20261102T172711-003, translated 2026-11-03
- claude-sonnet-5-5 — Machine translation, batch juvenile-act-20261102T172711-004, translated 2026-11-03
- claude-sonnet-5-5, corrected on review by claude-opus-5-5 — Machine translation corrected on review, 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