Japan's Supreme Court yesterday rejected the provision of bonus and retirement payments to non-regular employees, saying different treatment from regular employees was not unreasonable in two closely watched cases on their pay gaps, according to Kyodo News. Non-regular employees include dispatch workers (temporary workers), as well as indirect, part-time and fixed-term workers.

The Supreme Court's No. 3 Petty Bench overturned what was then a landmark high court ruling awarding a former female employee of Osaka Medical College approximately 1.09 million yen (USD 10,300), mostly in unpaid bonuses. The woman, who was in her 50s, argued it was unreasonable that she received no bonuses despite doing almost the same work as regular employees.

Separately, the Court also overturned a similar ruling that partly granted retirement payments to former employees on fixed-term contracts with Metro Commerce, a subsidiary of Tokyo Metro Co. which runs the capital's subway system.

In this case plaintiffs, women aged 66 through 73, argued that their employer’s denial of retirement allowances after working at kiosks for ten years or so breached Article 20 of the Labour Contract Law, which prohibits any “unreasonable disparity” in work conditions between regular and non-regular workers.

According to The Asahi Shimbun, the Supreme Court’s Third Petty Bench acknowledged that the tasks of regular and non-regular workers are “basically similar,” but pointed out that job responsibilities are not the same as regular workers fill in for non-regular workers when they are absent from work while others oversee the operations of several kiosks.

It stated that the company’s system of paying retirement benefits is meant “to secure personnel who can perform duties as regular employees.” For this reason, the court concluded it is not “unreasonable” to set different working conditions.

The rulings have come as a disappointment to the growing population of non-regular workers in Japan.