Tokyo official held over data leak

The Yomiuri Shimbun
The Metropolitan Police Department building in Chiyoda Ward, Tokyo

A Tokyo ward office official and an acquaintance were arrested Saturday on suspicion of leaking personal information obtained via the Basic Resident Registration Network System, the Metropolitan Police Department said.

The police suspect that personal data of about 20 people were leaked in the past year with the aim of helping a crime syndicate locate particular individuals.

The Yomiuri Shimbun
Naohisa Ichikawa

Naohisa Ichikawa, 32, an official of Suginami Ward Office and a resident of the ward, and his acquaintance Hiroki Sasaki, 34, of no fixed address, were arrested on suspicion of violating the Residential Basic Book Law.

According to the police, at the request of Sasaki, Ichikawa allegedly accessed the network — also known as Juki Net — to obtain addresses and other information relating to a man and a woman living outside Tokyo. Ichikawa is thought to have provided the data to Sasaki in or around April last year and February this year.

At the time, Ichikawa was working in the ward office residents’ division and was authorized to access Juki Net. The police believe Sasaki was asked by an acquaintance linked to a crime syndicate to locate certain people and obtained the relevant information from Ichikawa. The two men reportedly have been friends for 10 years.

Ichikawa is said to have had since 2018 access to information on residents outside the ward. The network terminal used by Ichikawa reportedly retains usage records, and the police are currently looking into the purposes of Ichikawa’s data access.

The ward office contacted the police in March over possible leakages after receiving a letter the previous month saying an official was leaking personal information by accessing the Juki Net system, according to the office.

Juki Net connects municipalities’ Residential Basic Books, which contain names, addresses, and dates of birth. The system, which began operating in August 2002, can be accessed by administrative agencies nationwide.

“We’re taking the matter very seriously,” Suginami Ward Mayor Satoko Kishimoto said.