The Supreme Court Ignored Article 28 of the Constitution/The Great Suppression Case of the Kansai District Ready-Mixed Concrete Industrial Union

2023.10.06 15:13 Nanami Nakagawa, Makoto Watanabe

What kind of judgment will the Supreme Court make regarding activities aimed at improving workers’ wages and workplace environments?

On September 11, 2023, there was a Supreme Court ruling of members of the industrial labor union “Kan-nama” as defendants.

“Kan-nama” is a labor union formed by drivers of mixer trucks that transport ready-mixed concrete in the Kansai region. Since 2018, police and prosecutors have been arresting union members in the Kansai region one after another, accusing them of “attempted extortion” and “forced obstruction of business.” The total number of arrests has grown to 89.

The most recent verdict concerns union actions at Murata Kenzai in Kyoto Prefecture in 2017. Murata Kenzai failed to provide its driver with an employment certificate, which is required to enroll a child in a nursery school, and when the Kan-nama asked Murata Kenzai to provide the certificate, the conduct was accused of intimidation and attempted extortion. The Osaka High Court overruled the Kyoto District Court’s verdict and acquitted some of the suspects on December 13, 2021,

In response, the First Petty Bench of the Supreme Court did not make a determination of guilt or innocence and requested the Osaka High Court to reconsider the case. The presiding judge of the First Petty Bench of the Supreme Court is Toru Sakai, former head of the Tokyo District Public Prosecutors Office. All five judges, including Mr. Sakai, agreed to remand the case.

Regarding the series of oppression cases against Kan-nama, the Osaka High Court also issued a not guilty verdict regarding the case that occurred in Wakayama. They upheld the rights of industrial unions as guaranteed by Article 28 of the Constitution.

Nevertheless, the Supreme Court did not take Article 28 of the Constitution into consideration. At a press conference after the ruling, union members and lawyers for the defendants said, “The Supreme Court tried to dodge its responsibility.”

Supreme Court in Chiyoda Ward, Tokyo (Photo by Nanami Nakagawa on September 11, 2023)

As soon as an employee joined the union, the company refused to issue a certificate

The origins date back to November 2017.

M was working as a mixer truck driver at Murata Kenzai in Kizugawa City, Kyoto Prefecture, at that time.  He started working as a daily driver at Murata Kenzai in 2012. His wife and he both worked. Since 2013, Murata Kenzai has provided him an “employment certificate” to submit to the nursery school every year in order to send his child to a nursery school.

In 2017, M became a member of the Kan-nama. In November, as usual, he asked Murata Kenzai to issue him an employment certificate. However, Murata Kenzai refused. The reason given was that the company would soon go out of business, but this is irrelevant as long as he is still employed at the time of submitting the certificate to Kizugawa City Hall. Masahiro Yasui, an executive committee member of the Kan-nama, and Osamu Yoshida, a member of the union, entered into negotiations with Murata Kenzai to request the issuing of M’s employment certificate. Director Yasumi Murata responded as a representative of Murata Kenzai.

During the trial, a major point of contention was whether Kan-nama’s attitude during negotiations went too far.

For example, On November 27,

​​Murata said that a city hall official had told her that a parent could use the nursery school even if he didn’t have an employment certificate. Yoshida called the relevant department at city hall on the spot and confirmed that a parent actually needed an employment certificate. He then urged Murata to call the department in charge, where she was informed that proof of employment was required.

However, during the call, Murata suddenly became ill and exhausted. She had to call an ambulance. Yasui and Yoshida suspected that the illness was a fake, saying, “There’s no way something like that could suddenly happen.”

Regarding this incident, the Kyoto District Court of First Instance ruled that they had “persistently made demands” even though it was “clear that she was sick,” and found it to be a threat.

The Osaka High Court described this as a ”sudden incident that occurred when Murata Kenzai was cornered in a scenario where it became difficult for Murata Kenzai to oppose the creation of job certificates.” Based on this, the judge ruled that ”it was not unreasonable to believe that she was faking an illness.”

The Supreme Court only stated that an investigation was required to establish if Kan-nama’s actions were excessive.

“Why can’t they make a decision? ”

The Supreme Court did not decide whether the actions of Kan-nama went too far. Moreover, it failed to rule on a more fundamental matter. The question is how to consider industrial union activities in light of Article 28 of the Constitution.

Among a series of oppression cases against Kan-nama, in the Wakayama incident, the union activities of the Kan-nama were accused of forcible obstruction of business and attempted extortion. In contrast, the judgment handed down by the Osaka High Court on March 6, 2023, was based on Article 28 of the Constitution. Presiding Judge Makoto Wada stated the following in his judgment:

“The Kansai District Ready-Mixed Concrete Branch (Kan-nama) of the All Japan Construction and Transport Workers Solidarity Union should, as an industrial union, be considered party to labor-related activities carried out by industrial employers and managers. The right to unionize is protected under Article 28 of the Constitution, while any attempts to infringe on that right are prohibited by law.”

At a press conference after the ruling, Kan-nama expressed its distrust of the Supreme Court judges who did not take into account the constitutionally guaranteed labor union activities.

Yoshida spoke with a disappointed expression.

“I expected the Supreme Court to rule that it was labor union activity, but it was remanded. Why can’t they make a decision? There had to be all of the evidence, so if they look at it all, they should be able to make their own decision. Honestly, I feel pathetic.”

Yasui spoke based on his own experience in union activities:

“We don’t need a labor union if they respond to a ‘favor.’ We have the right to contest and strike precisely because a ‘favor’ is not enough. Why didn’t the Supreme Court, which rules on constitutional issues, conclude this? That’s extremely unfortunate.”

Lawyer Fumi Kubori said it was unfortunate that, “the Supreme Court got away,” and expressed a sense of crisis that this case would be considered a crime.

“Article 28 of the Constitution guarantees the right to collective bargaining. This is an excellent opportunity for the labor union to demonstrate its capabilities. They were arrested and prosecuted for frequently visiting the company to obtain a certificate. The rationale for the labor union’s existence would be destroyed, and the person who acted dishonestly would prevail.”

“I believe it is the company that should be punished. The union negotiated persistently because the company acted in a dishonest manner. Then somehow, the union is subject to criminal penalties. This is a truly terrifying incident where something like this is considered a crime.”

At a press conference after the trial. From left: Attorney Fumi Kubori, Osamu Yoshida, Masahiro Yasui, Hiroyuki Mori (photo by Makoto Watanabe on September 11, 2023)

Things to Keep in Mind as a Justice

What kind of people are the five judges who issued the verdict? From the Supreme Court’s official website, I will excerpt their career and quote their “mindset as a judge.”

SAKAI Toru, chief judge

2010 Director, Special Investigation Department, Tokyo District Public Prosecutors Office

2020 Superintending Prosecutor, Tokyo High Public Prosecutors Office

2021 Justice of the Supreme Court


Things to Keep in Mind as a Justice

We are in the midst of dramatic changes in the social environments inside and outside the country, and due to these changes, cases brought to court have been becoming more complicated, difficult and diverse than before. For this reason, in order to make proper and reasonable judgments, I think that it is essential to learn new things proactively. I will perform my duties in a cordial manner, with a mindset to continue learning and a humble attitude, aiming to realize a justice system trusted by the people.


2012 Member (Chairperson) of the National Bar Examination Commission

2014 Professor of Waseda Law School

2017  Justice of the Supreme Court


Things to Keep in Mind as a Justice

I believe every day is a new learning experience. Based on this idea, I think I should bear in mind that I will make decisions from a fair and impartial standpoint while using everything I have.

MIYAMA, Takuya

2008 Director-General of the Judicial System Department, Minister’s Secretariat, Ministry of Justice

2017 President, Tokyo High Court

2018 Justice of the Supreme Court


Things to Keep in Mind as a Justice

As many cases in the Supreme Court involve complicated legal problems and/or issues on which different people make different subjective judgments, it is difficult for the Court to deal with the cases. I will strive to play an active role when the Supreme Court seeks a proper and appropriate interpretation and application of the law in each case as the highest court that primarily judges questions of law.


2011 Director General, Personnel Affairs Bureau, Supreme Court

2018 President, Osaka High Court

2021 Justice of the Supreme Court


Things to Keep in Mind as a Justice

I think it is important to face each and every case sincerely and straightforwardly and make a judgment, and to do so, it is important to read case records with an open mind and hear opinions of many people humbly.

OKA, Masaaki

2015 Vice President, Japan Federation of Bar Associations

2019 Outside Director, Sumitomo Mitsui Banking Corporation

2021 Justice of the Supreme Court


Things to Keep in Mind as a Justice

Article 76, paragraph (3) of the Constitution of Japan provides: “All judges shall be independent in the exercise of their conscience and the performance of their duties and shall be bound only by this Constitution and the laws.” I will always bear this in mind and take it as my fundamental code of conduct.


I will make effort day by day to improve and enhance my “conscience” that I should exercise; although I must be “independent”, always check myself to not become dogmatic; and, “in the performance of my duties,” cope with each and every case with all my energy, making it a principle to “read records and materials well, think with my own head, express my opinion plainly, and engage in multifaceted and deep deliberations with my fellow Justices.”


The Constitution also provides, in Article 81, that: “The Supreme Court is the court of last resort with power to determine the constitutionality of any law, order, regulation or official act.” Taking this into my heart, I will fulfill my constitutional responsibility.

From the left, Ryosuke Yasunami, Atsushi Yamaguchi, Toru Sakai (chief judge), Takuya Miyama, Masaaki Oka (from the official court website)

(Originally published in Japanese on September 11, 2023. Translation by Mana Shibata.)

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