mass action theoryglossary / MASS-ACTION THEORY mass-action theory. The principle that, as long as a labor union is functioning, it is vicariously liable for the joint acts of its members. 词条贡献者 译者Susanne,世界顶尖法学院国际税法专业,擅长翻译各种与联邦税务纠纷相关的法律文件。