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2016 (A) 442

2017.03.15
2016 (A) 442
Keishu Vol. 71, No. 3
Judgment on whether or not GPS investigation, which is a method of criminal investigation in which a vehicle’s location information is retrieved and monitored by secretly attaching a GPS terminal to the vehicle without its user’s consent, is a compulsory disposition that is not permitted to be conducted without a warrant
Case concerning charges of theft, burglary and bodily injury
Judgment of the Grand Bench, dismissed
Osaka High Court, Judgment of March 2, 2016
GPS investigation, which is a method of criminal investigation in which a vehicle’s location information is retrieved and monitored by secretly attaching a GPS terminal to the vehicle without its user’s consent, is a compulsory disposition that is not permitted to be conducted without a warrant, since it is a method of investigation that enables investigators to invade an individual’s private sphere against his/her reasonably inferred intention by secretly attaching to his/her belongings devices that enable an invasion of his/her privacy.
Article 35 of the Constitution and Article 197, paragraph (1) of the Code of Criminal Procedure



The Constitution of Japan

Article 35. The right of all persons to be secure in their homes, papers and effects against entries, searches and seizures shall not be impaired except upon warrant issued for adequate cause and particularly describing the place to be searched and things to be seized, or except as provided by Article 33.

Code of Criminal Procedure

Article 197 (1) With regard to investigation, such examination as is necessary to achieve its objective may be conducted; provided, however, that compulsory dispositions shall not be applied unless special provisions have been established in this Code.
The final appeal is dismissed.
Of the grounds for final appeal submitted by the counsels, KAMEISHI Michiko et al.: the ground based on an alleged violation of Article 35 of the Constitution obviously does not affect the conclusion of the judgment of prior instance as described below; the ground based on an alleged inconsistency with precedents refers to precedents whose circumstances were different from those of this case and which thus are not appropriate to be referred to in this case; and the remaining grounds, including those based on alleged violations of the Constitution, are substantially allegations of mere violations of laws and regulations and do not constitute grounds for a final appeal as referred to in Article 405 of the Code of Criminal Procedure.

The following explains the Court’s ruling as to whether or not the judgment of prior instance on the legality of the method of criminal investigation in which a vehicle’s location information is retrieved and monitored by secretly attaching a GPS terminal to the vehicle without its user’s consent (hereinafter referred to as “GPS investigation”) was appropriate, considering the views of the court of prior instance.

1. Outline of the case

According to the judgment of prior instance and the decision dated June 5, 2015 of the court of first instance, in this case a GPS investigation whereby vehicles’ locations were tracked and their movements monitored was conducted by keeping GPS terminals attached for a period of approximately six and a half months, from around May 23, 2013 to around December 4, 2013, to a total of nineteen cars and other vehicles which were likely to be used not only by the accused and his accomplices but also by the accused’s female friends, without their consent and without obtaining a warrant, as part of the investigation of certain theft cases which were suspected of having been committed by the accused together with his accomplices, in order to elucidate a full picture of their criminal acts, including the presence or absence and level of systematicity and the role played by the accused in the group (hereinafter this investigation is referred to as the “GPS Investigation”).

2. Summary of the conclusions of the court of first instance and the court of prior instance

(1) The court of first instance concluded that the GPS Investigation constituted a compulsory disposition having the nature of inspection (the proviso to paragraph (1) of Article 197 of the Code of Criminal Procedure) and that the GPS Investigation was seriously illegal in that it was conducted without obtaining an inspection permit. The court then rejected the admissibility of the evidence obtained directly from the GPS Investigation and the evidence closely related to the GPS Investigation. However, the court found the accused guilty based on the remaining evidence.

(2) The judgment of prior instance did not reject the admissibility of the remaining evidence whose admissibility had not been rejected by the judgment of first instance, and rejected the appeal by the accused, ruling that the court did not find the GPS Investigation seriously illegal, on such grounds as: that the level of privacy invasion was not necessarily high under the circumstances, considering such facts as that the information that could be obtained by the GPS Investigation was limited to the locations of the vehicles to which GPS terminals were attached; that, under the circumstances, the GPS Investigation was considered necessary to be conducted in combination with shadowing and stakeouts to monitor the activities of the accused’s and others; that, even if there might be room for considering that the GPS Investigation constituted a compulsory disposition and was illegal in that it was conducted without a warrant, the GPS Investigation was considered to have satisfied the substantive requirements for obtaining a warrant; that, by around the time the GPS Investigation was conducted, no judicial rulings had been made or established that considered GPS investigation to constitute a compulsory disposition, which made it difficult to find that the police officers had intention to evade the provisions related to the principle of warrant in conducting the GPS Investigation; and that it could not possibly be understood that GPS investigation violated the principle requiring that compulsory dispositions be authorized by statutory grounds and could thus not be conducted lawfully with or without a warrant.

3. The Court’s rulings

The Court has examined and found the rulings described in 2(2) above to be unacceptable, for the following reasons:

(1) GPS investigation, which is conducted to retrieve and monitor current location information of the target vehicle, makes it possible, by its nature, to monitor the location and movements of the target vehicle and its user in detail, not only on public roads but also in places and spaces where personal privacy should strongly protected. Since such a method of investigation inevitably involves the continuous, comprehensive monitoring of the person’s activities, it may invade personal privacy. In addition, unlike such methods of investigation as grossly monitoring locations on public roads or taking photos using a camera, GPS investigation should be considered to involve an invasion by public authorities of the private sphere, in that it is conducted by secretly attaching devices that enable such invasion to personal belongings.

(2) Article 35 of the Constitution provides for the “right … to be secure in their homes, papers and effects against entries, searches and seizures.” It is reasonable to understand that the target of the protection given by this provision is not limited to “homes, papers and effects” but includes the right not to be “invaded” into the private sphere that is equivalent to these. It should then be understood that GPS investigation is a disposition that is not permitted to be conducted without a warrant, since GPS investigation, which is, as described above, a method of investigation that invades a person’s private sphere against the person’s reasonably inferred intention by attaching devices that enable personal privacy invasion to the person’s belongings, violates material legal interests guaranteed by the Constitution by suppressing the person’s intention and, as such, constitutes a compulsory disposition that is not permitted under the Code of Criminal Procedure without special statutory grounds (see Supreme Court, 1975 (A) 146, Decision of the Third Petty bench of March 16, 1976, Keishu Vol. 30, No. 2, p. 187), and since it is generally difficult to consider that there are reasons for placing GPS investigation in the category of dispositions that do not require a warrant, such as immediate arrest.

(3) While the judgment of prior instance mentioned the possibility of obtaining a warrant, it also ruled that it could not possibly be understood that GPS investigation violated the principle requiring that compulsory dispositions be authorized by statutory grounds and could thus not be conducted lawfully with or without a warrant. Let us consider this point as well in terms of the effect this ruling would have on the practices of investigation and the issuance of warrant.

While GPS investigation has a nature similar to “inspection” under the Code of Criminal Procedure in that GPS investigation involves the monitoring of the location and movements of the target vehicle by reading the screen of the information device, it is difficult to deny that GPS investigation also has a nature that cannot be covered entirely by “inspection” in that GPS investigation involves the tracking of the location of the target vehicle and its user by attaching a GPS terminal to the target vehicle. Even assuming that an inspection permit is required or a search permit is required in addition to an inspection permit to conduct GPS investigation, as GPS investigation inevitably involves the continuous, comprehensive monitoring of the target vehicle user’s activities through tracking the location of the target vehicle to which a GPS terminal is attached, it may not be possible, by merely specifying the vehicle to which a GPS terminal should be attached and the charge(s), to prevent excessive monitoring of the vehicle user’s activities that are irrelevant to the alleged facts, and the intention of requiring a judge to examine a request for a warrant may not be fulfilled. Furthermore, since GPS investigation would be meaningless unless conducted secretly without being known to the suspect, it is impossible to expect that a warrant should be shown to the suspect in advance. To take a compulsory measure under the Code of Criminal Procedure, a corresponding warrant must in principle be shown to the person who is to undergo the measure in order to ensure due process (Article 222, paragraph (1) and Article 110 of the said code). Even assuming that showing a warrant in advance is not an absolute requirement if its intention can be achieved by other means, a failure to secure alternative means to ensure due process would leave behind problems in terms of the guarantee of due process.

Possible means to resolve these problems would generally include, among others, limiting the period during which GPS investigation is permitted to be conducted, requiring third-party witnesses, and subsequent notification. It is understood that what means to select by giving consideration also to the effectiveness of the investigation is left primarily to the legislative body, in light of the intention of the proviso to paragraph (1) of Article 197 of the Code of Criminal Procedure. Assuming that GPS investigation is permitted by statutory interpretation as a compulsory disposition under the Code of Criminal Procedure, it would be necessary to attach various conditions to the warrant issued by a judge in order to resolve the aforementioned problems. However, permitting a compulsory disposition that cannot be approved unless the judge who is in charge of examining the request for a warrant makes choices of appropriate conditions from among various choices at his/her discretion on a case-by-case basis would not be in line with the intention of the proviso to the said paragraph which provides, “compulsory dispositions shall not be applied unless special provisions have been established in this Code.”

As described above, it is questionable to issue a warrant for GPS investigation as set forth in the Code of Criminal Procedure by assuming that “special provisions have been established [for GPS investigation] in this Code” as provided for in the proviso to paragraph (1) of Article 197 of the said code. Assuming that GPS investigation is a promising method of investigation that will continue to be used commonly in the future, it is desirable that legislative action be taken that will conform to the principles of the Constitution and the Code of Criminal Procedure by focusing on the characteristics of GPS investigation.

(4) The rulings of the court of prior instance described in 2(2) above, which are contrary to the above, erred in the interpretation and application of the Constitution and the Code of Criminal Procedure and are unacceptable.

4. However, the judgment of first instance is reasonable in that while it rejected the admissibility of the evidence obtained directly from the GPS Investigation and the evidence closely related to the GPS Investigation, it accepted the admissibility of the remaining evidence, ruling that such evidence was not considered to be closely related to the GPS Investigation, and found the accused guilty. The conclusion of the judgment of prior instance that upheld the judgment of first instance is not erroneous, and it is obvious that the aforementioned errors of the judgment of prior instance in the interpretation and application of the relevant law do not affect the judgment.

Accordingly, the Court unanimously decides as set forth in the main text in accordance with the proviso to paragraph (1), Article 410 and Articles 414 and 396 of the Code of Criminal Procedure. However, there is a concurring opinion of three of the justices, OKABE Kiyoko, OTANI Takehiko and IKEGAMI Masayuki.

The concurring opinion of the justices, OKABE Kiyoko, OTANI Takehiko and IKEGAMI Masayuki, is as follows:

We agree with the view expressed in the Court’s opinion that legislative action focused on the characteristics of GPS investigation should be taken. However, since it is inferred that it will take some time before GPS investigation is enshrined in law even if it is decided that such legislation will be concretely discussed, we believe that, pending such legislation, investigators should not be entirely denied to conduct GPS investigation by having a judge examine their request for a warrant.

Naturally, even if such conduct of GPS investigation is permitted, it will be permitted by a warrant that is different from what should properly be obtained. Such conduct of GPS investigation should thus be permitted only in cases where it can be approved by highly advanced judicial judgment based on the spirit of Article 1 of the Code of Criminal Procedure. Therefore, a high degree of necessity is required in the sense that continuous, comprehensive monitoring of the target vehicle user’s activities is essential for the investigation of very limited types of extremely serious offenses. Furthermore, even in such cases, a warrant must of course be requested and issued after giving full consideration to the points made in the Court’s opinion. Thus, even assuming that there is room for the issuance of a warrant as described above, an extremely careful judgment must be made under very limited special circumstances.

In the presence of the Public Prosecutors, SAKAKIBARA Kazuo and UKAWA Haruhiko
Justice TERADA Itsuro

Justice OKABE Kiyoko

Justice OTANI Takehiko

Justice OHASHI Masaharu

Justice ONUKI Yoshinobu

Justice ONIMARU Kaoru

Justice KIUCHI Michiyoshi

Justice YAMAMOTO Tsuneyuki

Justice YAMASAKI Toshimitsu

Justice IKEGAMI Masayuki

Justice OTANI Naoto

Justice KOIKE Hiroshi

Justice KIZAWA Katsuyuki

Justice KANNO Hiroyuki

Justice YAMAGUCHI Atsushi
(This translation is provisional and subject to revision.)