◇賃金格差是正を求め東京地裁に提訴しました

　学校法人桜丘では、担当授業時間数が同じであっても、専任教員と非常勤講師との間に約４倍（年齢によってはそれ以上）の年収格差があります。この格差是正を求め、当組合の組合員は、２０２５年８月１９日、学校法人桜丘を被告として、東京地方裁判所に損害賠償請求訴訟を提起しました。

　学校は教員にとって職場であり、当然のことながら労働関係法規の遵守が求められます。「労働契約法」（旧第２０条）および「パートタイム・有期雇用労働法」（第８条）は、有期雇用・短時間雇用の濫用的利用を抑制し、雇用の安定と格差是正を図ることを目的として整備されてきました。これらの法律および「同一労働同一賃金ガイドライン」は、業務の内容・責任の程度・配置変更の範囲などに照らして、不合理な待遇差を設けることを禁じています。

　非常勤講師も、日々の授業に加え、教材研究・教材作成、定期試験や小テストの作成・採点、ノートチェック、成績処理、生徒指導、進路相談など、多岐にわたる業務に従事しています。学級副担任業務に就くこともあれば、部活動の顧問に名前を入れられることもあります。他方、専任教員のなかには長年にわたり担任業務を担わない者もおり、両者の業務内容や責任の差は、雇用形態によって一律に線を引けるものではありません。

　それにもかかわらず、給与制度上、非常勤講師の月給は担当授業時間（コマ数）に応じて算定されるのみで、それ以外の多岐にわたる業務に対する明確な対価が制度上組み込まれていません。約４倍にものぼる待遇差を正当化するに足る業務内容・責任の差異が客観的・具体的に存在するのか、そして給与の決定基準・ルール自体の相違が合理的といえるのかが、本訴訟で問われています。

　また、学校法人桜丘では、勤続２０年を超える非常勤講師も在籍しており、校内の非常勤講師の比率は約５割にのぼります。これは、非常勤講師が「臨時的雇用」としてではなく、長期雇用を前提に活用されている実態を示すものです。それにもかかわらず、生徒数の減少等を理由とする一方的な不利益変更がなされることもあり、非常勤講師は不安定な立場に置かれ続けています。

　教員の労働条件の改善は、教育の質の向上に不可欠です。専門職としての教員が職務上の自律性を発揮できる労働環境を整備することは、「教員の教育の自由」と「教育活動の民主化」を支える基盤でもあります。雇用形態を理由とした待遇格差は重要な人権問題であり、公教育の場としての子どもたちの学び舎を守ることにもつながる課題です。

　本件訴訟と、職場環境の改善に向けた取り組みへのご理解と、署名へのご協力を心よりお願い申し上げます。

＝＝＝
東京地裁への提訴にあたって行った記者会見を、弁護士.JPさんに報じて頂いています。こちらもぜひご一読ください。
https://www.ben54.jp/news/2589
＝＝＝

◇ Lawsuit Filed at the Tokyo District Court Seeking Redress of Wage Disparity

　At Sakuragaoka Educational Foundation, even when the number of class hours taught is the same, there exists an annual income gap of approximately fourfold (and in some age brackets even greater) between full-time teachers and part-time instructors. Seeking to rectify this disparity, members of our union filed a damages lawsuit against Sakuragaoka Educational Foundation at the Tokyo District Court on August 19, 2025.
A school is a workplace for its teachers, and naturally, compliance with labor-related laws and regulations is required. The Labor Contract Act (former Article 20) and the Part-Time and Fixed-Term Employment Act (Article 8) have been established to curb the abusive use of fixed-term and part-time employment, and to promote employment stability and the redress of disparities. These laws, together with the “Guidelines on Equal Pay for Equal Work,” prohibit unreasonable differences in treatment in light of the content of duties, the degree of responsibility, the scope of changes in assignment, and other relevant factors.
　Part-time instructors, too, engage in a wide range of duties beyond classroom teaching: preparing teaching materials, creating and grading periodic examinations and short quizzes, checking notebooks, processing grades, providing student guidance, offering career counseling, and more. They sometimes serve as assistant homeroom teachers and are at times listed as advisors to extracurricular clubs. On the other hand, some full-time teachers do not serve as homeroom teachers for many years. The differences in duties and responsibilities between the two cannot be drawn along a simple line based on employment status.
　Nevertheless, under the current compensation system, the monthly salary of part-time instructors is calculated solely based on the number of class hours taught, and there is no clear remuneration built into the system for the wide range of duties they perform beyond the classroom. Whether differences in the content of duties and responsibilities sufficient to justify a roughly fourfold disparity in treatment objectively and concretely exist, and whether the differences in the salary determination rules themselves can be deemed reasonable, are the central questions being addressed in this lawsuit.
　Furthermore, at Sakuragaoka Educational Foundation, there are part-time instructors with more than twenty years of continuous service, and part-time instructors account for approximately fifty percent of the teaching staff on campus. This reflects the reality that part-time instructors are not utilized as “temporary employees” but rather under the assumption of long-term employment. Despite this, unilateral disadvantageous changes are sometimes imposed on the grounds of declining student numbers, and part-time instructors continue to be placed in an unstable position.
　Improving the working conditions of teachers is essential to enhancing the quality of education. Establishing a working environment in which teachers, as professionals, can exercise occupational autonomy is the foundation that supports both “academic freedom in teaching” and the “democratization of educational activities.” Wage disparity based on employment status is a significant human rights issue, and it is a matter that also bears on protecting the schools where our children learn as places of public education.
　We sincerely ask for your understanding of this lawsuit and of our efforts to improve the working environment, and for your cooperation in signing the petition.

═══
A press conference held on the occasion of filing the lawsuit at the Tokyo District Court has been reported by Bengoshi.JP. We hope you will also read the article.
https://www.ben54.jp/news/2589
═══