The Japanese people and their lawmakers should start discussing whether Japan should abolish the emperor system and become a republic because it legitimizes discrimination based on social status, a law professor said Saturday at an event to oppose National Foundation Day.

Masahiko Shimizu, a professor of constitutional law at Nippon Sport Science University, acknowledged that the Constitution stipulates that the Emperor is the symbol of the state and of the unity of the people, which is different from the Meiji Constitution, which stated that sovereignty lies with the Emperor.

"The emperor system is discrimination based on social status, with traces of feudalism," Shimizu said, however.