Yokohama District Public Prosecutors Office Prosecutor Kobayashi and "National Tax and Police Receiving Anonymous Reports"
On July 27, 2026, members of the Prosecutors Union called the Special Criminal Division of the Yokohama District Public Prosecutors Office.
The purpose was neither to elicit details of the investigation into Mr. Shigenori Kanemoto nor to pressure the assigned prosecutor. Rather, it was to provide the Yokohama District Public Prosecutors Office with information and evidentiary materials, following reports of investment fraud from multiple union members who invested in N Co., Ltd. utilizing the angel tax system.
When I told the receptionist, "I'd like to be connected to Prosecutor Kobayashi," the call was transferred to another person. The person on the phone introduced themselves as follows:
Mr. Kobayashi: "I am Prosecutor Kobayashi."
However, Mr. Kobayashi has not clarified whether he was the prosecutor in charge of the Shigenori Kanemoto case. This article also does not conclude that Mr. Kobayashi was the prosecutor in charge of the case.
The problem comes after that.
The members of the prosecutors' union tried to communicate that multiple individuals who invested in N Corporation had done so believing the administrative inquiry records of Defendant Toshibuki Nakano and the explanation by Certified Public Accountant Satoshi Saito that it was a legal tax saving.
If Company N has no actual business operations and investors were induced to contribute funds through false explanations, then investors, including Shigenori Kanemoto, may not be accomplices to tax evasion, but rather victims of investment fraud.
However, Prosecutor Kobayashi ended the call without listening to the information to the end and without providing instructions on where to submit the evidentiary documents.
The prosecutors' union has preserved this approximately 8-minute-and-40-second recording as evidence.
What Yokohama District Public Prosecutors Office Prosecutor Kobayashi checked first was not the details of the damage, but the source of the information.
Immediately after a prosecutor union member stated that they had heard that Prosecutor Kobayashi was in charge, Mr. Kobayashi first confirmed the source of the information.
Prosecutor Kobayashi: "Who did you hear from that I'm handling this?"
When the union member answered, "I am a union member," further questions followed.
Prosecutor Kobayashi: "Who specifically are you referring to?"
It is not unnatural in itself to verify the credibility of an informant or the identity of the caller. It is also understandable that investigative agencies are wary of false or harassing reports.
However, at this point, the prosecutors' union side has not yet explained the specific details of the information they are trying to provide.
Before asking who leaked the information, couldn't you have asked whether that information concerned new criminal victimization or evidence?
Yokohama District Public Prosecutors Office Prosecutor Kobayashi himself mentioned that investigative information is leaking outside
Approximately 3 minutes and 19 seconds after the start of the call, Prosecutor Kobayashi stated the following effect.
Prosecutor Kobayashi: "Things related to the investigation and such—given the situation, it's really not good for that kind of information to get out."
At this stage, the prosecutors' union side has not yet questioned about the Mamizuka memo, the name of the assigned prosecutor, or the leak of investigative information prior to the arrest.
The Prosecutors Union does not conclude from this statement that the Yokohama District Public Prosecutors Office admitted to leaking information.
However, why did Prosecutor Kobayashi state, even before we pursued the information leak, that "the mere fact that matters related to the investigation are getting out is not good"?
Information has been received that before Shigenori Kanemoto's arrest, not only Prosecutor Kobayashi's name, but also the name of another prosecutor, transactions viewed as problematic in the investigation, and theories regarding conspiratorial relationships had been circulating among the parties involved.
On the day of his arrest on July 23, footage of Shigenori Kanemoto was used, with TBS displaying "Yokohama City, January of this year" and ANN-affiliated news displaying "Asahi Ward, Yokohama City, March."
If they truly believe that the leaking of investigative information is "undesirable," they should investigate not only the identification of the informant, but also the flow of information within the Yokohama District Public Prosecutors Office and the press club.
Attempting to explain the possibility of investment fraud involving N Corporation leads to the call being disconnected
The members of the prosecutors union explained that multiple union members invested in Company N just like Mr. Shigenori Kanemoto.
Furthermore, we conveyed that the defendant Toshiyuki Nakano had shown investors detailed records of administrative inquiries made to the Small and Medium Enterprise Agency, the Tokyo Metropolitan Government, Kagoshima Prefecture, and tax offices, and that certified public accountant Satoshi Saito had explained that investments in Company N were a legal use of the angel tax system.
In response, Prosecutor Kobayashi stated as follows:
Prosecutor Kobayashi: "What is the purpose of Mr. Yamamoto's phone call just now? If there is such a discussion, it might be related to the investigation, so I cannot give you any answers."
The prosecutors' union side clearly stated that they were not seeking a response, but rather would now explain the purpose of providing the information.
When I tried to explain that if Company N had no actual business operations thereafter, it might constitute fraud against the investors, Prosecutor Kobayashi interrupted the conversation halfway through.
Prosecutor Kobayashi: "Actually, considering the things that keep coming up in our conversation, and now the name Kanemoto has come up as well—since there's a possibility it's related to the investigation, we can't just keep talking like this."
The prosecutors' union side stated, "You don't have to answer what you cannot answer," and "As long as an investigation is conducted."
Even so, Prosecutor Kobayashi responded as follows.
Prosecutor Kobayashi: "We cannot accommodate that."
Prosecutor Kobayashi: "I am going to hang up the phone."
Finally, when the prosecutors' union side stated that the investors were demanding the return of their investment funds, Prosecutor Kobayashi made the following statement and ended the call.
Prosecutor Kobayashi: "Since this is related to the case currently under investigation, I cannot answer any further questions over the phone. I'm very sorry, but I will be hanging up now."
Didn't the Yokohama District Public Prosecutors Office refuse not just to answer, but even to receive the information?
It goes without saying that the investigation status of individual cases cannot be disclosed to unrelated third parties.
I also understand that the name of the assigned prosecutor, the seized evidence, the suspect's statement, and future investigation policies cannot be explained to outside parties.
However, refusing to disclose the details of the investigation and refusing to listen to information regarding new crimes until the end are two different issues.
What the prosecutor union side was asking for was not internal information from the Yokohama District Public Prosecutors Office.
This was new information brought in from the outside, stating that multiple individuals who invested in Company N did so by relying on administrative inquiry records and explanations from a certified public accountant, and are now claiming to be victims of investment fraud.
Prosecutor Kobayashi has not explicitly stated that "the prosecution does not accept anonymous information."
However, they repeatedly raised concerns about not knowing the name or contact information, did not listen to the gist of the information provided until the end, and failed to provide information on where to send documents, how to submit evidence, or which department receives damage reports.
As a result, anonymous victim information is being blocked at the entrance of the Yokohama District Public Prosecutors Office.
The National Tax Agency specifies that it will check all anonymous information.
The National Tax Agency has provided an online form titled "Provision of Information Regarding Omissions in Taxation and Collection."
On this form, the informant's name, age, relationship to the subject, and contact information are all optional.
Furthermore, the National Tax Agency specifies as follows:
We have verified the contents of all the provided information.
Information sources are also optional, and data such as account books, receipts, contracts, passbooks, and other documents can be attached.
Reference:National Tax Agency: Provision of information regarding tax assessment and collection omissions
It is reported that the Tokyo Regional Taxation Bureau and the Yokohama District Public Prosecutors Office are jointly investigating the Shigenori Kanemoto case.
On the other hand, the National Tax Agency has announced that it accepts information even if it is anonymous and reviews every single case. Meanwhile, at the Yokohama District Public Prosecutors Office, explanations of the victim information are cut short simply because the specific name and contact information of the informant are unknown.
Should the information entry points be this different between two state agencies handling the same case?
The police are also utilizing anonymous tips in investigations while limiting the target cases.
The National Police Agency and the Metropolitan Police Department also operate the Anonymous Tip Hotline while limiting the types of cases eligible.
This is a system in which information provided anonymously by citizens is reported to the police by a private organization commissioned by the National Police Agency, to be utilized for investigations and other purposes.
Targets include crimes involving criminal organizations such as organized crime groups (buryokudan), special fraud, human trafficking, and offenses related to criminal infrastructure.
Reference:Metropolitan Police Department "Regarding the Anonymous Tip Hotline"
The police anonymous hotline does not cover all crimes. Even so, rather than instantly dismissing the information just because it is anonymous, a system is in place to verify the value of the information and utilize it for investigations.
Both the national tax agency and the police have systems for receiving anonymous information.
Yet, if only the prosecutors, who take over cases from the police and national tax authorities and possess their own direct investigative powers, prioritize verifying the identity of the informant and fail to listen to the substance of the information to the end, there is a clear gap in the system for receiving criminal information.
If the Yokohama District Public Prosecutors Office becomes the dumping ground for national tax cases, please accept the opposition documents as well.
The prosecutors' union has long referred to the structure in which prosecutors simply accept the factual determinations made by the National Tax Agency as the "National Tax Agency's pass-the-buck service."
We will accept the incriminating materials collected by the National Tax Agency.
I will also receive the fund chart created by the National Tax Agency.
We also take on cases prosecuted by the National Tax Agency.
However, contrary information and new reports of victimhood—such as those accepted anonymously by the National Tax Agency itself—are rejected at the outset on the grounds that the names are unknown.
Then it would no longer be a joint investigation, but rather a service that just delivers the script chosen by the National Tax Agency.
There is no legal obligation to unconditionally conduct in-person interviews with every single member of the prosecutors' union. Nor is it realistic to simultaneously interview tens of thousands of people.
However, in order to determine whose stories need to be heard, we must at least receive the gist of the information.
If you hang up before hearing the information, you can't even judge its necessity.
Open Questions to Prosecutor Kobayashi of the Yokohama District Public Prosecutors Office
- Are you recording the phone call received by the Special Criminal Division of the Yokohama District Public Prosecutors Office from the Prosecutors Union on July 27, 2026?
- Do you acknowledge the fact that the person who answered the phone identified themselves as "Prosecutor Kobayashi"?
- Even if Prosecutor Kobayashi was not in charge of the Shigenori Kanemoto case, was he in a position to receive and forward information related to the case?
- Why did you repeatedly confirm the source of the prosecutor's name and the specific names of the union members before the summary of the information you were about to provide?
- Does the Yokohama District Public Prosecutors Office generally not accept crime information if the informant's name and contact information are unknown?
- If there are laws, circulars, or internal regulations that do not accept anonymous information, can their names and contents be made public?
- If there is no such rule, what is the reason for not listening to this phone call through to the end?
- Why didn't you distinguish between not being able to respond to individual cases and receiving information about new crimes?
- Have you reported to the responsible department or your superior the possibility that multiple individuals who invested in Corporation N are claiming to be victims of investment fraud?
- Have you considered the recruitment and system explanations by Defendant Kazuyoshi Nakano and Mr. Satoshi Saito as new investigative matters?
- What is the reason why you did not guide them through the phone call, the submission destination for documents, the method for submitting evidence, and the contact point for reporting the damage?
- Will you establish a system in the future to receive crime information provided anonymously or under a pseudonym, and determine its necessity after reviewing the content?
- Will you receive the recordings and written materials preserved by the prosecutors' union on the premise of concealing the source?
Open Questionnaire to the Supreme Public Prosecutors Office and the Ministry of Justice
- Does the Public Prosecutors Office have a nationwide common contact point for receiving anonymous information regarding general crimes?
- If it exists, why hasn't it been announced in a way that the public can understand?
- If it does not exist, will you establish an anonymous information provision system similar to that of the National Tax Agency or the National Police Agency?
- Will you instruct public prosecutors' offices nationwide not to refuse the filing of new crime reports or the provision of evidence on the grounds that the investigation details of individual cases cannot be disclosed?
- Shall we establish a protocol to verify the content of the information before identifying the informant?
- Will you conduct an inspection to verify whether the recent telephone response by the Yokohama District Public Prosecutors Office was appropriate?
If you want to reduce crime, you should listen more to information that doesn't fit your narrative.
The prosecutors' union does not unconditionally accept anonymous information as fact.
Anonymous information is also accepted at the intake stage. Unverified parts are clearly stated as unverified. It is cross-checked with recordings, documents, remittance records, and multiple testimonies. Then, public questions are submitted to the competent authorities.
This is the basic stance of the prosecutors' union.
The standard required of investigative agencies should be higher than that.
If they only listen to information that fits their own case construction and dismiss information indicating other crimes as being of unknown identity, then the investigation becomes not a clarification of the truth, but a reinforcement of the story they created first.
I have heard information that describes Shigenori Kanemoto as a criminal.
Information identifying Shigenori Kanemoto as a victim of investment fraud is cut off mid-sentence.
If that screening is truly taking place, isn't what the Yokohama District Public Prosecutors Office is trying to protect not public safety, but their own narrative?
I ask that Prosecutor Kobayashi confirm the matters not discussed this time, along with the records, without fail on the next occasion.
