How did the police and prosecutors try to destroy Kan-nama? Tansa has collected testimonies from union members who were detained and interrogated.

This time, we interviewed Satoru Yamamoto, who, while working as a mixer truck driver, serves as an executive committee member of Kan-nama, providing advice to workers and engaging with union activities.

In 2018, when a large-scale crackdown on Kan-nama began, Yamamoto became the target of the Shiga Prefectural Police Organized Crime Department. To protect the safety of workers and passersby, Yamamoto checked construction sites for dangers and violations of laws and regulations, so called “Compliance Activity”. When he found violations, he pointed them out. This was considered to be an obstruction of construction work, and he was arrested on suspicion of intimidation and obstruction of business.

“Oh, here they come”

I was arrested at the end of November 2018. It happened all of a sudden. I had just woken up at 6 a.m., turned on the kitchen light and was preparing to make lunch when they came. My apartment is on the second floor, and I heard footsteps.

I thought, “Oh, here they come.” From the end of 2017, everyone in Kan-nama was thinking, “Maybe things are getting out of hand.” I wasn’t, but there were quite a few members who were being watched by plainclothes detectives. In fact, Chairman Yuji Yukawa was arrested on the same day. This is when the large-scale crackdown on Kan-nama began.

Nine investigators entered my one-room apartment all at once. They were from the Shiga Prefectural Police. When I asked the investigator who the leader was,  they answered, “Hayashi from the Organized Crime Department.” They started a raid, but they didn’t have anything to take. In the end, they only took my smartphone and cards. I was forced to give the password to my smartphone, and they confiscated my credit cards, ETC (electronic toll collection) card, and other items that were not related to the charges.

The purpose was not to investigate, but to force withdrawal

The interrogation was not to investigate the charges, but to force withdrawal from Kan-nama. I was detained for 100 days, but the forced withdrawal was the hardest. “You’ll be arrested again if you keep going like this. So think about your own path, isn’t it time to quit?” I wrote down in a notebook what I was told during my detention.

The police interrogation took place at Hikone Police Station. The person in charge was a man named Nishizawa from the Shiga Prefectural Police Headquarters Second Investigation Division. He said, “The Kan-nama executives have saved up a lot of money. You guys are nobody,” and “Don’t you think about quitting with others?” He also said, “If you do “Compliance Activity” in Shiga, we’ll arrest you as many times as it takes.”

The prosecutor was Mayuko Yoko. She asked questions like, “Why don’t you quit? What are you thinking?”, “Are you going to take this opportunity to leave the union? What does your family think?”, “Are you going to continue ‘Compliance Activity’ and get arrested again?”, and “Some of the members in the union are feeling stressed by union activities. What do you think, Mr. Yamamoto?”

They were trying to make me quit and making other members quit as well.

In order to prevent fatal accidents

I have been a mixer driver since 2000. With the introduction of a friend, I became a member of Kan-nama in 2012 at the age of 44.

Originally, even if I drove 18 days a month, my salary was less than 300,000 yen. But after I became a member of Kan-nama, my working conditions improved and I started earning more than 400,000 yen. I was surprised that my take-home pay increased by about 100,000 yen for the same number of days. I now knew exactly how much I would be paid depending on how much I worked.

Until then, I was told by my superiors at work and would say, “Yes, yes, I understand.” I was the kind of person who would just suck up to them, but now I’ve completely changed 180 degrees. I don’t think of myself as superior, but I think and act for the sake of workers and citizens.

One of the union activities is “Compliance Activity.” Construction sites are in the city, right? There are fatal accidents, and there are civilians who are just passing by. What I was most worried about was causing trouble to civilians. That’s the worst thing. Also, I tried my best to get people to think about the safety of workers at construction sites. I told the companies to follow the law. Dump trucks and other vehicles come and go from huge construction sites, and many deadly incidents occur there, similar to slamming into pedestrians. The most frequent location for work-related accidents is construction sites. I think I need to engage in more “Compliance Activity” when I hear stories like that. Accidents that result in death are, after all, the most terrifying.

But I was arrested for that.

The hardest part

The hardest part was that my girlfriend at the time left me. We had been together for 14 years, but I got arrested…

After I was arrested, I left my house keys with her. When I was released on bail, my smartphone was confiscated, so I borrowed a phone from a police officer and called her. “I just came out, can you bring me the house keys?” But she seemed a little strange. “Why do I have to take them?” In the end, a fellow union member came to pick me up, and I received the keys from her at a convenience store near my house. We ended up never seeing each other again.

I was scared and didn’t ask her why she left me like that. I wondered if she didn’t like the fact that I called from the police or if something had happened while I was under arrest. I don’t know if the police or the prosecutor’s office contacted her. But I didn’t want to burden her anymore. I still wonder, but I haven’t talked to her.

Expanding to other regions

It’s tough when the people around me and the society don’t understand our union activities. It’s difficult to figure out how to make them understand, but I’m trying one thing at a time.

I’m currently working on setting up various chapters in Nagoya and increasing the number of union members. In Nagoya, truck drivers’ wages are extremely low. They are about the same as in Kansai 20 years ago. There is also a lot of unpaid overtime. There are many building construction projects and linear construction projects, but mixer drivers don’t have any breaks. That’s why they came to Kan-nama for advice.

I didn’t know about it at first either, but I thought that all of that had to change. I’m supporting them by teaching them about the union’s aspirations and how to organize. The number of union members is increasing in Nagoya as well.

Education on labor rights in schools

Since I joined Kan-nama, I have been studying and participating in meetings, such as meetings of various labor unions and demonstrations by civic groups. Recently, there have also been anti-war demonstrations for Gaza.

However, nowadays, we don’t learn about such activities, especially about labor unions, in school. In the past, there were strikes at the national railway, and trains in my neighborhood were often stopped. Office workers heading to the station would say things like, “The train’s stopped, so I’ll take the day off from work.” But now it’s the opposite, and it seems like many people find strikes a nuisance.

I think it starts with education. We should start teaching about industrial unions from elementary school onwards, and teach labor rights.

I have been involved in labor unions, and I was arrested and detained in this case, but I am not ashamed of it at all. Recently, there have been many wrongful conviction cases in the news. I think the people are starting to notice the wrongdoings of investigative authorities. We will continue to fight and win an acquittal for everyone.

I want everyone to know that this was a wrongful conviction.

[Reporter’s Postscript] Prosecutors who mistakenly believe they are superior, but the exact opposite is union activity / Reporter Nanami Nakagawa

During his detention, Yamamoto recorded the details of his interrogation, including the date, time, location, weather, and the name of the interrogator. He also wrote down not only the details of the interrogation, but also the content of casual conversations and the attitude of the interrogator.

The comments made by the interrogators were clearly not intended as an interrogation of a suspect. They were using the arrest and detention to pressure him to quit the union with other members.

Yamamoto did not admit to the charges and refused to withdraw from the union. As a result, he was detained for 100 days and lost his long-time partner. This is nothing but a violation of human rights through the abuse of power.

Why would an interrogator take such an outrageous action? Doesn’t he mistakenly think that he has become superior by having the backing of state power? This is the complete opposite of Yamamoto, who said, “I don’t think of myself as superior, but I think and act for the sake of workers and citizens.”

Kan-nama has filed a lawsuit seeking state compensation for the unjust arrest, interrogation, and detention. On March 7, 2025, a witness hearing for the state compensation lawsuit would be held at the Tokyo District Court.

Four prosecutors and detectives who had interrogated the union members of Kan-nama appeared as witnesses in court. Among them was Mayuko Yoko, the prosecutor who handled Yamamoto’s case.

Prosecutor Yoko pressed Yamamoto on why he would not quit the union and what he was thinking. The reason why Yamamoto would not quit the union was as he explained in his interview with Tansa. Now it is Prosecutor Yoko’s turn to testify in court about why she forced Yamamoto to quit the union and what she was thinking.

(Originally published in Japanese on May 5, 2025. Translation by Mana Shibata.)

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