TOKYO -- Japanese police have introduced new guidelines allowing undercover investigations where officers pose as applicants for illegal "dark jobs," prompting experts to call for third-party oversight and legislative debate to prevent abuse of the changes.

Under these "disguised identity investigations," a first for Japan, officers will assume fake identities to investigate crimes. The operations target illicit work linked to offenses such as robbery and fraud. The National Police Agency (NPA) guidelines, outlined in 10 points, detail the procedures officers must follow when conducting these investigations.

The guidelines specifically define "disguised identity investigations" as police activities where fake documents with fabricated names, addresses and other personal details are presented when applying for jobs posted by criminal recruiters. To initiate such operations, officers must submit a proposal which requires approval from the prefectural police chief. These plans will include the reason for the investigation, its structure, duration and the number of fake identification documents required. The number of fake IDs created will be limited to what is specified in the plan. Senior officers, including chief inspectors and those above in rank, will be appointed by the chief to oversee and manage the operations, and fake IDs must be securely stored in a separate, locked location to prevent misuse.

While not included in the guidelines, the NPA maintains that the forgery of identification documents, which would be illegal under ordinary circumstances, will not be considered unlawful in such investigations, as the Penal Code exempts acts carried out as part of legitimate business operations from punishment.

Katsuyoshi Kato, a professor of criminal law at Senshu University's Graduate School of Law, acknowledged that the guidelines provide some safeguards, saying, "The specification of investigative scope and procedures in the guidelines is commendable to a certain extent, as it provides some level of restraint on the expansion of powers." However, he points out weaknesses in the oversight system, stating, "According to the guidelines, checks will be conducted internally, and it could lead to broader applications." He added, "It feels strange that the program started with guidelines rather than a discussion on whether legislation is necessary."

Kato also highlighted that in countries like Germany, France and the U.S., similar systems are regulated by laws or guidelines that limit the scope of undercover investigations. However, there have been cases where these powers were used in cases beyond their intended scope. He suggested that Japan consider establishing a system where third parties, such as judges, can review the legitimacy of such investigations.

Hiromi Naitoh, an associate professor of criminal procedure law at Kumamoto University, agrees on the need for third-party oversight. He argues that information on undercover investigations should be disclosed publicly, similar to the requirements under the Act on Communications Interception for Criminal Investigation.

Naitoh also referenced a Supreme Court ruling which declared police use of GPS tracking devices without a warrant to be illegal. He said, "At this stage, it's unclear what problems may arise from these undercover operations. More debate was needed on whether guidelines alone are sufficient or if legal provisions are necessary."

The NPA has so far only stated that it will consider disclosing the number of undercover investigations conducted under these guidelines.

(Japanese original by Masakatsu Yamasaki, Tokyo City News Department)