The Tokyo Summary Court trial dealing with the labor case involving Dentsu Inc., which stemmed from the suicide of a young overworked employee two years ago, is set to wrap up quickly with a ruling this Friday. In the one-day hearing held last month, the advertising agency accepted the prosecutors' charge that it subjected four employees, including the suicide victim, to illegal amounts of overtime. President Toshihiro Yamamoto apologized for the death of the 24-year-old female employee and promised to develop a corporate culture that prioritizes protecting worker health. The Dentsu case must not just end in exposing the illegal practices at the firm alone. It must serve as a catalyst for greater efforts by businesses and the government to eradicate the excessively long work hours that imperil the health of many corporate employees.

Matsuri Takahashi, who joined Dentsu in spring 2015, jumped to her death from a company dorm on Christmas Day that year. A labor inspection office later recognized her suicide as work-related, having found that she was working 105 hours of overtime a month before she developed depression. A lawyer for Takahashi's family reportedly said that management told her to underreport her overtime so it would look like the number of hours were within the limit agreed to by the company and its labor union.

In their opening statement Sept. 22, the prosecutors said that long overtime work, including late at night and on days off, was prevalent in Dentsu offices under its "client first" policy. In 2014, for example, some 1,400 Dentsu employees every month worked beyond the overtime limit set by the labor-management agreement.