A former Tokyo District Public Prosecutors Office special investigator and the anonymous whistleblowing system that prosecutors lack
In July 2026, it was reported that a 48-year-old male prosecutor who had served in the Special Investigation Department of the Tokyo District Public Prosecutors Office was suspected of having an inappropriate relationship with a woman he had interrogated in a case.
It is said that the relationship with the woman began after the investigation ended.
However, their encounter is not an encounter between equal private individuals.
One is the public prosecutor, who can influence arrests, prosecutions, non-prosecutions, and other criminal dispositions.
The other is a woman who was being interrogated as a suspect by that prosecutor.
Furthermore, it is reported that the male prosecutor is suspected of inviting the woman to a hotel secured with public funds in order to question a person involved in a separate case, and staying overnight with her.
It is also reported that he is suspected of demanding valuables such as watches and wireless earphones from a woman, accepting them, and using a card in the woman's name.
The Supreme Public Prosecutors Office acknowledged the investigation, stating, "Based on the facts that have come to light, we will deal with the matter strictly."
Some weekly magazines even report the male prosecutor's real name and photograph, as well as suspicions of a relationship with another woman and a double life. However, because unconfirmed information and the privacy of the woman involved are included, this article does not state the male prosecutor's name.
We cannot simply wrap this matter up by describing it as just "an affair by a married prosecutor."
The issues in question are the relationship with someone met through investigative powers, the private use of public funds, the exchange of money and valuables, the impact on criminal dispositions, the unauthorized use of investigative information, and the supervisory system within the public prosecutor's office.
The issue with the former Tokyo District Public Prosecutors Office Special Investigation Department prosecutor is not his private life, but his use of investigative authority.
National public servants also have private lives.
The state should not have unlimited oversight over relationships outside the workplace.
However, the other party in this case is a woman who was interrogated by a male prosecutor in the line of duty.
The male prosecutor was in a position to access information that the general public cannot know, such as the details of the female's case, her statements, address, family, assets, vulnerabilities, and the outlook for criminal disposition.
Even if a relationship begins after an investigation concludes, the power dynamics and psychological effects that arose during the investigation do not disappear simply because the case is closed.
Were there any connections between decisions not to prosecute, pending dispositions, reduction of the scope of prosecution, or other criminal dispositions, and subsequent relations?
Weren't you exchanging private messages before getting involved?
Did you use the personal information obtained during the investigation for private communication?
Did the woman not feel that she would suffer disadvantages in the case if she refused the relationship with the prosecutor?
We cannot simply ignore these and write it off as "the affair happened after the investigation ended."
Suspicion of using a publicly funded hotel for personal purposes
According to reports, the male prosecutor is suspected of inviting a woman to a hotel in Tokyo paid for with public funds to interview a person involved in a case, and staying overnight.
If true, the problem isn't just about the relationship between men and women.
Funding source for hotel expenses.
Purpose of reservation.
Details of public expense settlement.
Usage report.
Guest Information
Access log.
It is necessary to check whether there were any falsifications in official documents or accounting records regarding these matters.
If an employee of a private company uses a company-paid hotel room intended for an investigation for personal accommodation, it may be subject to disciplinary action and a demand for reimbursement.
There is no reason why only prosecutors, who interrogate others and strictly investigate the existence of expenses, should be exempt from explaining their expenses by simply saying, "It was an inappropriate relationship."
If the demands for money and valuables and the use of a credit card in a woman's name are true, it goes beyond the scope of an "affair."
Reports say that a male prosecutor is suspected of demanding and receiving items such as a watch and wireless earphones from a woman, and of using a credit card in the woman's name at stores and other locations.
If these are facts, we must check the price of the money and goods, the method of demand, the power dynamics of the relationship, and the connection to criminal penalties.
Was it merely a gift?
Did he make the demand by leveraging his position as a prosecutor?
Was it in exchange for criminal punishment or the provision of information?
Was there the cardholder's consent regarding the use of the card?
Whether criminal liability is established is determined by the evidence and specific facts.
However, there is no reason to handle this merely through internal disciplinary procedures within the legal and prosecutorial authorities and not consider it as a criminal case.
If you are dismissed for disciplinary reasons, you cannot become a lawyer for three years.
If a prosecutor is dismissed for disciplinary reasons, the usual career transition of "quitting the prosecution and immediately becoming a lawyer" is not possible.
Article 7 of the Attorney Act stipulates that if a public official is dismissed by disciplinary action, any person for whom three years have not elapsed since the date of the disposition is disqualified from becoming an attorney.
Reference:e-Gov Law Search "Attorney Act"
Additionally, for national public servants who have been dismissed for disciplinary reasons, based on Article 12 of the National Public Service Retirement Allowance Act, measures may be taken to withhold all or part of their retirement allowances, taking into consideration their duties and responsibilities, the nature and severity of the wrongdoing, and the impact on public trust in the civil service.
The total non-payment of retirement benefits is not automatically decided. However, in cases where public funds, investigative authority, and the relationship with the suspect are at issue, there would be no reason not to consider restricting payment.
Prosecutorial scandals are unlikely to come to light without anonymous information.
Victims and witnesses of misconduct by prosecutors frequently request anonymity.
The other party is a prosecutor with the power to arrest and prosecute.
Anyone involved in an incident would fear the impact on the criminal penalties for themselves or their family members.
If they are inside the prosecutor's office, personnel affairs, transfers, evaluations, and isolation in the workplace are what they fear.
As press reporters, they might fear losing access to prosecutorial reporting.
In fields like this, important information never comes to light if you use a system that requires informants to use their real names from the very beginning.
The National Tax Agency receives anonymous information, and the police have also institutionalized anonymous reporting.
On the National Tax Agency's "Information Provision on Tax and Collection Omissions," the name and contact information of the informant are optional.
The National Tax Agency explicitly states regarding the provided information, "We check the contents of all cases."
Reference:National Tax Agency: Provision of information regarding tax assessment and collection omissions
The police have also established an anonymous tip hotline for target cases such as criminal organizations, special fraud, and human trafficking.
Reference:Metropolitan Police Department "Regarding the Anonymous Tip Hotline"
The Supreme Public Prosecutors Office also has an information provision desk of the Inspection and Guidance Department concerning inappropriate conduct by prosecutors and public prosecutor's assistant officers.
However, it is clearly stated that this office does not handle inquiries regarding the investigation details or disposition results of individual cases.
In other words, while there is technically a reporting hotline for prosecutorial staff to anonymously report misconduct within their own ranks, there appears to be no nationwide, clearly defined system for anonymously submitting crime information or evidence regarding general cases investigated by the prosecution.
This time, Prosecutor Kobayashi of the Yokohama District Public Prosecutors Office did not listen to the anonymous investment fraud information to the end, nor did he direct me to the evidence submission counter.
Looking at the issue of the former special investigation prosecutor suspected of having a relationship with a woman he interrogated, the need to establish a system for receiving anonymous information is clear.
Concluding it as a "mere affair" would serve as self-protection for the prosecutors.
If this matter is treated as an affair between a married man and a woman, it might be possible to avoid criminal punishment and have them quietly leave the organization through suspension or voluntary retirement.
There are also reports and testimonies that, in the past, senior prosecutors and male prosecutors whose relationships with subordinates, junior colleagues, administrative officials, and female reporters were viewed as problematic were transferred to obscure positions and quietly retired.
However, this time it is a woman whom the prosecutor interrogated as a suspect.
A hotel provided at public expense.
Suspicion of demanding and receiving money and valuables.
Suspected use of a card in a woman's name.
The connection between investigative authority and private relationships.
If these are facts, this is not a matter that should be brushed off as a precedent-setting case of "quiet quitting."
Open Questionnaire to the Supreme Public Prosecutors Office and the Ministry of Justice
- What evidence confirmed that the relationship between the male prosecutor and the woman began after the investigation ended?
- Did you check whether personal communication, visits, or an emotional relationship had started since the investigation began?
- Did male prosecutors influence the criminal disposition regarding women?
- Have you re-verified the non-prosecution, the scope of the case filing, the statements in the protocol, and other procedures?
- Are you preserving the usage records, billing statements, and guest information of the publicly funded hotel?
- Did you investigate whether the hotel usage constitutes an unauthorized use of public funds?
- Have you confirmed the fact that you requested and received watches, earphones, and other valuables?
- Have you checked the consent and the usage amount regarding the use of the card in a woman's name?
- Are you considering criminal liability such as extortion of money and goods using one's official position, provision of benefits, and bribery?
- Are you using or sharing investigation information, personal information, and statements for personal relationships?
- Did you investigate other romantic involvements or similar reports within the prosecutor's office?
- Will you publish the criteria for considering disciplinary dismissal, suspension, and other penalties?
- In the case of dismissal for disciplinary reasons, is the disqualification period under Article 7 of the Attorney Act appropriately applied?
- Will you consider the non-payment of all or part of the retirement allowance based on Article 12 of the National Public Service Retirement Allowance Act?
- Will you establish a permanent channel where victims, witnesses, and internal staff can anonymously submit information and evidence?
- Will you introduce a National Tax Agency-style operation to check the contents of all anonymous information?
- Will you establish a system to prevent the whistleblower's identity from being leaked to the person being reported, their department, and the press club?
- Will you make public the investigation results, disciplinary actions, and whether it has become a criminal case, while taking the victimized woman's privacy into consideration?
It doesn't make sense to accept only information monitoring the prosecution if it isn't under real names.
The prosecutor asks the citizens for a statement.
We are seeking insider information regarding organized crime, tax evasion, and fraud.
On the other hand, when information is received regarding their own scandals or information that contradicts their case construction, they verify the informant's identity first, and if it is anonymous, they turn it away at the door.
Under that system, facts that are inconvenient for the prosecution are less likely to come to light.
Anonymous information is not necessarily true.
That is precisely why we check after receiving it.
Both the national tax authority and the police incorporate this mindset into their systems.
If prosecutors alone protect themselves from false information by refusing to listen to anonymous tips, while remaining unable to find internal scandals or the seeds of wrongful convictions, what they are protecting is not the fairness of investigations, but the silence of the organization.
Do not reduce the former special prosecutor's issue to merely an "affair"; investigate all aspects including investigative powers, public funds, money and gifts, personal information, and criminal penalties.
And please establish a system by the prosecutors themselves that allows the next victim or whistleblower to deliver initial information without having to provide their real name.
