The president of advertising giant Dentsu Inc. on Friday admitted in court that it allowed employees to work illegal levels of overtime, leading the high-profile case sparked by the suicide of former employee Matsuri Takahashi closer to its rare public conclusion.

In the first and only hearing of the trial, prosecutors demanded that Dentsu pay a mere ¥500,000 fine. A ruling is expected on Oct. 6.

“The precious life of Matsuri Takahashi had been lost. I sincerely apologize to her and her bereaved family,” Dentsu President Toshihiro Yamamoto told a news conference after the trial, referring to the overworked young employee who jumped to her death from the company dorm on Christmas Day in 2015. “We failed to fulfill the social responsibility of a company.”

In cases of karōshi (death by overwork), firms that agree to pay fines typically go through a quiet summary indictment that leads to a quick settlement. Not so in Dentsu’s case. Dentsu was summarily indicted on July 5, but the court decided on July 12 that the ruling was “inadequate” and that the highly influential company should face an open trial.

Hiroshi Kawahito, a lawyer representing Takahashi’s mother, praised the decision, saying it helped spread corporate awareness that turning a blind eye to illegal overtime is a serious violation of the law.

“Dentsu allowed illegally long working hours for a very long time, causing many cases of karoshi. Unlawful (working) environments will improve by having corporate responsibility judged under the criminal justice system,” Kawahito said at a separate news conference Friday at the labor ministry.

“The president of Dentsu stood at today’s trial, pleading guilty, regretting and promising to never make the same mistake again. It was important that the president himself made promises at the court.”

Since October 2015, Dentsu forced four employees work more than the 50-hour monthly maximum specified by its labor-management agreement, the written indictment said. Among the four employees was Takahashi, then 24, who took her own life in just her ninth month with Dentsu. The Labor Standards Inspection Office recognized her death as work-related in September 2016.

Takahashi’s suicide, which was induced by more than 100 hours per month of overtime and power harassment, dragged the issue of karoshi back into the national spotlight.

According to the labor ministry, there were 84 cases of suicide or attempted suicide determined to be work-related in 2016.

Following Takahashi’s suicide, Dentsu began introducing new policies, such as turning the lights off after 10 p.m. and providing free breakfast to encourage work in the morning instead of late at night.

“Dentsu has been saying that it’s working toward improving the work environment since even before my daughter joined the company. Knowing that, I can’t trust what the president has said today,” said Matsuri’s mother Yukimi Takahashi, who attended the news conference with Kawahito.

To improve Dentsu’s working environment, the president, executives, and all employees at the company, as well as its stockholders, clients and Japan as a whole, must work together to eliminate the practice of illegal overtime, Takahashi added.

Information from Kyodo added