Request for voluntary disclosure based on an "enquiry sheet"
Within the limits of their competence, public authorities may also collect electronic information based on requests for voluntary disclosure. This refers to a non-compulsory form of cooperation where compliance with the request cannot be enforced (88), thus relieving the public authorities from the duty of obtaining a court warrant.
To the extent such a request is directed at a business operator and concerns personal information, the business operator has to comply with the requirements of the APPI. According to Article 23(1) of the APPI, business operators may disclose personal information to third parties without consent of the individual concerned only in certain cases, including where the disclosure is "based on laws and regulations" (89). In the area of criminal law enforcement, the legal basis for such requests is provided by Article 197(2) of the CCP according to which "private organisations may be asked to report on necessary matters relating to the investigation." Since such an "enquiry sheet" is permissible only as part of a criminal investigation, it always presupposes a concrete suspicion of an already committed crime (90). Moreover, since such investigations are generally carried out by the Prefectural Police, the limitations pursuant to Article 2(2) of the Police Law (91) apply. According to that provision, the activities of the police are "strictly limited" to the fulfilment of their responsibilities and duties (that is to say the prevention, suppression and investigation of crimes). Moreover, in performing its duties, the police shall act in an impartial, unprejudiced and fair manner and must never abuse its powers "in such a way as to interfere with the rights and liberties of an individual guaranteed in the Constitution of Japan" (which include, as indicated, the right to privacy and data protection) (92).
Specifically with respect to Article 197(2) of the CCP, the National Police Agency ("NPA") – as the federal authority in charge, among others, of all matters concerning the criminal police – has issued instructions to the Prefectural Police (93) on the "proper use of written inquiries in investigative matters". According to this Notification, requests must be made using a pre-established form ("Form No. 49" or so-called "enquiry sheet") (94), concern records "regarding a specific investigation" and the requested information must be "necessary for [that] investigation". In each case, the chief investigator shall "fully examine the necessity, content, etc. of [the] individual enquiry" and must receive internal approval from a high-ranking official.
Moreover, in two judgments from 1969 and 2008 (95), the Supreme Court of Japan has stipulated limitations with respect to non-compulsory measures that interfere with the right to privacy (96). In particular, the court considered that such measures must be "reasonable" and stay within "generally allowable limits", that is to say they must be necessary for the investigation of a suspect (collection of evidence) and carried out "by appropriate methods for achieving the purpose of [the] investigation" (97). The judgments show that this entails a proportionality test, taking into account all the circumstances of the case (e.g. the level of interference with the right to privacy, including the expectation of privacy, the seriousness of the crime, the likelihood to obtain useful evidence, the importance of that evidence, possible alternative means of investigation, etc.) (98).
Aside from these limitations for the exercise of public authority, business operators themselves are expected to check ("confirm") the necessity and "rationality" of the provision to a third party (99). This includes the question whether they are prevented by law from cooperating. Such conflicting legal obligations may in particular follow from confidentiality obligations such as Article 134 of the Penal Code (concerning the relationship between a doctor, lawyer, priest, etc. and his/her client). Also, "any person engaged in the telecommunication business shall, while in office, maintain the secrets of others that have come to be known with respect to communications being handled by the telecommunication carrier" (Article 4(2) of the Telecommunication Business Act). This obligation is backed-up by the sanction stipulated in Article 179 of the Telecommunication Business Act, according to which any person that has violated the secrecy of communications being handled by a telecommunications carrier shall be guilty of a criminal offence and punished by imprisonment with labour of up to two years, or to a fine of not more than one million yen (100). While this requirement is not absolute and in particular allows for measures infringing the secrecy of communications that constitute "justifiable acts" within the meaning of Article 35 of the Penal Code (101), this exception does not cover the response to non-compulsory requests by public authorities for the disclosure of electronic information pursuant to Article 197(2) of the CCP.