Labor authorities have determined the suicide of a Toyota Motor Corp. employee in 2017 was caused by harassment from his superior, a lawyer for the man's family said Tuesday.

The worker, who died at the age of 28, developed an adjustment disorder after he was constantly verbally abused by his superior, who had called him names like "moron" and told him "You'd be better off dead," the lawyer, Yoshihide Tachino, said.

After completing his master's degree at the University of Tokyo's graduate school, he joined the automaker in April 2015 and started designing vehicles at Toyota's headquarters in Toyota, Aichi Prefecture, from March 2016.

He took a leave of absence from July 2016 after being diagnosed with an adjustment disorder. Although he was assigned to another section upon returning to work in October that year, the superior was still sitting close to him, Tachino said.

After returning to work, his hands were often trembling, and he became prone to simple mistakes. The worker said to people around him, "I want to die" before committing suicide in his room at an employee dormitory in October 2017, Tachino said.

During an in-house probe, the superior broadly admitted to making abusive comments, according to Tachino.

In March this year, the worker's family applied with a local labor standards office for compensation for work-related deaths, claiming there were words and deeds by his superior that "deviated from the scope of work-related instructions."

The labor office decided on Sept. 11 that his death was caused by a work-related incident subject to compensation, recognizing most of the claims filed by the family.

Usually, in cases where a worker stops seeing a doctor after returning to work, labor offices do not recognize subsequent incidents as work-related, judging the worker to be recovered.

"There were symptoms even after he returned to work, and it is significant that the labor office admitted there was a causal relationship between the suicide (and his work)," Tachino said.

The family is planning to seek damages from Toyota, according to Tachino.

"If the company properly handled the situation, the superior's harassment could have been prevented," the worker's family said in a statement. "We want the company to make an effort to improve the working environment in light of this occasion where (the death of the worker) was recognized as work-related."

A Toyota official said, "We take the decision of the labor office seriously and will further work to prevent work-related accidents and promote employees' health management."

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