JapanLiability for violating communication secrecy?
In Japan, violating communication secrecy is a criminal offense punishable by up to 2 years imprisonment or a fine of up to ¥1 million under the Penal Code.
What the Law Says
Japanese law strictly protects the secrecy of communications, including letters, emails, and other private transmissions. Violating this secrecy without lawful authority is a defined criminal offense.
Article 133 of the Penal Code criminalizes unauthorized interception, opening, or disclosure of sealed correspondence addressed to another person.
The law applies regardless of whether the communication is physical (e.g., a letter) or electronic (e.g., encrypted email), as long as it is sealed and intended to remain private.
Intent is required: the offender must knowingly and intentionally violate the secrecy — accidental or incidental access is not punishable under this provision.
Statutory TextA person who opens, without justifiable grounds, a sealed letter or other document addressed to another person shall be punished by imprisonment with work for not more than two years or a fine of not more than one million yen.
— Penal Code, s. 133 — Opening of Sealed Correspondence
What to Do
Do not open, read, forward, or disclose sealed or private communications addressed to others — even if unintentionally received.
If you receive someone else’s private message or letter by mistake, do not access its contents; return it unopened or notify the sender immediately.
Employers or system administrators must ensure lawful, transparent, and limited monitoring of employee communications — only with clear consent or statutory authorization.
Consult a qualified attorney before taking any action that may involve accessing another person’s private communications.
Sources
Not legal advice. This article is general information based on publicly available sources, written for educational purposes. Laws change and individual situations vary. Consult a licensed attorney in your jurisdiction before acting on anything you read here. Last reviewed: 2026-06-08.