First of all, as regards its material scope, the APPI distinguishes personal information from personal data, with only certain of the provisions of the Act being applicable to the former category. According to Article 2(1) of the APPI, the concept of "personal information" includes any information relating to a living individual which enables the identification of that individual. The definition distinguishes two categories of personal information: (i) individual identification codes; and (ii) other personal information whereby a specific individual can be identified. The latter category also includes information which by itself does not enable identification but, when "readily collated" with other information, allows the identification of a specific individual. According to the PPC Guidelines (16), whether information can be considered as "readily collated" shall be judged on a case by case basis, taking into consideration the actual situation ("condition") of the business operator. This will be assumed if such collation is (or can be) performed by an average ("normal") business operator using the means available to that operator. For instance, information is not "readily collated" with other information if a business operator needs to make unusual efforts or commit illegal acts to obtain the information to be collated from one or more other business operators.

Third, in addition to civil law (tort) remedies, a data subject may file a complaint with a public prosecutor or judicial police official with respect to APPI violations that can lead to criminal sanctions. Chapter VII of the APPI contains a number of penal provisions. The most important one (Article 84) relates to non-compliance by the PIHBO with PPC orders pursuant to Article 42(2) and (3). If a business operator fails to comply with an order issued by the PPC, the PPC Chair (as well as any other government official) (66) may forward the case to the public prosecutor or judicial police official and in that way trigger the opening of a criminal procedure. The penalty for the violation of a PPC order is imprisonment with labour for up to six months or a fine of up to 300 000 yen. Other provisions of the APPI providing for sanctions in case of APPI violations affecting the rights and interests of data subjects include Article 83 of the APPI (regarding the "providing or using by stealth" of a personal information database "for the purpose of seeking […] illegal profits") and Article 88(i) of the APPI (regarding the failure by a third party to correctly inform the PIHBO when the latter receives personal data in accordance with Article 26(1) of the APPI, in particular on the details of the third party's own, prior acquisition of such data). The applicable penalties for such violations of the APPI are, respectively, imprisonment with work for up to one year or a fine of up to 500 000 yen (in case of Article 83) or an administrative fine of up to 100 000 yen (in case of Article 88(i)). While the threat of a criminal sanction is already likely to have a strong deterrent effect on the business management that directs the PIHBO's processing operations as well as on the individuals handling the data, Article 87 of the APPI clarifies that when a representative, employee or other worker of a corporate body has committed a violation pursuant to Articles 83 to 85 of the APPI, "the actor shall be punished and a fine set forth in the respective Articles shall be imposed on the said corporate body". In this case, both the employee and the company can be imposed sanctions up to the full maximum amount.

As an exercise of public authority, government access in Japan must be carried out in full respect of the law (legality principle). In this regard, the Constitution of Japan contains provisions limiting and framing the collection of personal data by public authorities. As already mentioned with respect to processing by business operators, basing itself on Article 13 of the Constitution which among others protects the right to liberty, the Supreme Court of Japan has recognised the right to privacy and data protection (72). One important aspect of that right is the freedom not to have one's personal information disclosed to a third party without permission (73). This implies a right to the effective protection of personal data against abuse and (in particular) illegal access. Additional protection is ensured by Article 35 of the Constitution on the right of all persons to be secure in their homes, papers and effects, which requires from public authorities to obtain a court warrant issued for "adequate cause" (74) in all cases of "searches and seizures". In its judgment of 15 March 2017 (GPS case), the Supreme Court has clarified that this warrant requirement applies whenever the government invades ("enters into") the private sphere in a way that suppresses the individual's will and thus by means of a "compulsory investigation". A judge may only issue such warrant based on a concrete suspicion of crimes, i.e. when provided with documentary evidence based on which the person concerned by the investigation can be considered as having committed a criminal offence (75). Consequently, Japanese authorities have no legal authority to collect personal information by compulsory means in situations where no violation of the law has yet occurred (76), for example in order to prevent a crime or other security threat (as is the case for investigations on grounds of national security).

The Constitution also guarantees the right of access to the courts (Article 32) and the right to sue the State for redress in the case where an individual has suffered damage through the illegal act of a public official (Article 17).

In order to facilitate complaint handling, the NPA has issued a "Notice" to the Police and Prefectural Public Safety Commissions on the proper handling of complaints regarding the execution of duties by police officers. In this document, the NPA stipulates standards for the interpretation and implementation of Article 79 of the Police Law. Among others, it requires the Prefectural Police to establish a "system for handling complaints" and to handle and report all complaints to the competent Prefectural Public Safety Commission "promptly". The Notice defines complaints as claims seeking correction "for any specific disadvantage that has been inflicted as the result of an illegal or inappropriate behaviour" (115) or "failure to take a necessary action, by a police officer in his/her execution of duty" (116), as well as any "grievance/discontent about inappropriate mode of duty execution by a police officer". The material scope of a complaint is thus broadly defined, covering any claim of unlawful collection of data, and the complainant does not have to demonstrate any harm suffered as a result of a police officer’s actions. Importantly, the Notice stipulates that foreigners (among others) shall be provided with assistance in formulating a complaint. Following a complaint, the Prefectural Public Safety Commissions are required to ensure that the Prefectural Police examines the facts, implements measures "according to the result of the examination" and reports on the results. Where the Commission considers the examination to be insufficient, it shall issue an instruction on the handling of the complaint, which the Prefectual Police is required to follow. Based on the reports received and the measures taken, the Commission notifies the individual indicating, among others, the measures taken to address the complaint. The NPA Notice stresses that complaints should be handled in a "sincere manner" and that the result should be notified "within the scope of time […] deemed appropriate in the light of the social norms and common sense".

Third, an individual who disagrees with a seizure decision (warrant) (118) concerning his/her personal data by a judge, or with the measures by the police or prosecution executing such a decision, may file a request for that decision or such measures to be rescinded or altered (Articles 429(1), 430(1), (2) of the CCP, Article 26 of the Wiretapping Act) (119). In the case where the reviewing court considers that either the warrant itself or its execution ("procedure for seizure") is illegal, it will grant the request and order the seized articles to be returned (120).

Fourth, as a more indirect form of judicial control, an individual who considers that the collection of his/her personal information as part of a criminal investigation was illegal may, at his/her criminal trial, invoke this illegality. If the court agrees, this will lead to the exclusion of the evidence as inadmissible.

Finally, under Article 1(1) of the State Redress Act a court may grant compensation where a public officer who exercises the public authority of the State has, in the course of his/her duties, unlawfully and with fault (intentionally or negligently) inflicted damage on the individual concerned. According to Article 4 of the State Redress Act, the State's liability for damages is based on the provisions of the Civil Code. In this respect, Article 710 of the Civil Code stipulates that liability also covers damages other than those to property, and hence moral damage (for instance in the form of "mental distress"). This includes cases where the privacy of an individual has been invaded by unlawful surveillance and/or the collection of his/her personal information (e.g. the illegal execution of a warrant) (121).

In any event, the Administrative Organ has to take a written decision within a certain period (30 days, which under certain conditions can be extended by an additional 30 days). If the request is rejected, only partially granted, or if the individual for other reasons considers the conduct of the Administrative Organ to be "illegal or unjust", the individual may request administrative review based on the Administrative Complaint Review Act (141). In such a case, the head of the Administrative Organ deciding on the appeal shall consult the Information Disclosure and Personal Information Protection Review Board (Articles 42, 43 APPIHAO), a specialised, independent board whose members are appointed by the Prime Minister with consent of both Houses of the Diet. According to the information received, the Review Board may carry out an examination (142) and in this respect request the Administrative Organ to provide the retained personal information, including any classified content, as well as further information and documents. While the ultimate report sent to the complainant as well as the Administrative Organ and made public is not legally binding, it is in almost all cases followed (143). Moreover, the individual has the possibility to challenge the appeal decision in court based on the Administrative Case Litigation Act. This opens the way for judicial control of the use of the national security exception(s), including of whether such an exception has been abused or is still justified.

Member States and their organs are required to take the measures necessary to comply with acts of the Union institutions, as the latter are presumed to be lawful and accordingly produce legal effects until such time as they are withdrawn, annulled in an action for annulment or declared invalid following a reference for a preliminary ruling or a plea of illegality. Consequently, a Commission adequacy decision adopted pursuant to Article 45(3) of Regulation (EU) 2016/679 is binding on all organs of the Member States to which it is addressed, including their independent supervisory authorities. At the same time, as explained by the Court of Justice in the Schrems judgment (148) and recognised in Article 58(5) of the Regulation, where a DPA questions, including upon a complaint, the compatibility of a Commission adequacy decision with the fundamental rights of the individual to privacy and data protection, national law must provide it with a legal remedy to put those objections before a national court which, in case of doubts, must stay proceedings and make a reference for a preliminary ruling to the Court of Justice (149).