Osaka Gov. and Nippon Ishin no Kai leader Ichiro Matsui is suing Niigata Gov. Ryuichi Yoneyama for allegedly damaging his honor through tweets that seemed to imply Matsui was a dictator.

The comments were originally made last October, after a female high school student filed a suit against the Osaka Prefectural Government alleging her school had demanded she dye her naturally brown hair black.

That month Yoneyama said through his Twitter account that the Osaka governor is ultimately responsible for matters in the prefecture's schools, and that the directive to dye her hair appeared to be in line with a Nippon Ishin leader who attacks other party members voicing different opinions, forcing them to be obedient. Matsui was named in the tweet.