The young man suspected of being behind an attack on Japanese Prime Minister Fumio Kishida last weekend sued the government in 2022 over his ineligibility to run for parliament.
Kimura Ryuji, 24, is suspected to be behind an explosive device which last Saturday blew up at a site in the western city of Wakayama where Kishida was set to give a campaign speech.
The suspect is said to have threw a cylindrical object that loudly exploded ahead of Kishida's speech, causing panic. He was arrested on the spot.
Although Ryuji refused to speak to police, he has hired a lawyer, unlike last year when he sued over rules disqualifying him from running for a seat in Japan's parliament.
Court records from last year cited by Japanese broadcaster NHK showed Ryuji filed a lawsuit at the Kobe district court in central Japan claiming $700 in compensation due to "psychological trauma."
Ryuji claimed government rules barring him from seeking a seat last July in the Diet (parliament) caused him trauma.
"The election law violates the Constitution," Ryuji claimed in his suit, citing how age restrictions prevented him from running.
He also challenged the requirement for a candidate to submit money in order to run.
Under Japanese election laws, candidates must be at least 30 years of age and deposit up to 3 million yen ($22,000) to run for the Diet's upper house.
Ryuji appealed in Osaka High Court after a Kobe court dismissed the case.
Ryuji also "expressed anger" over a state funeral held for former Prime Minister Abe Shinzo, who was assassinated at a campaign rally last year.
Tetsuya Yamagami, 42, confessed to the assassination, as he blamed the former premier for causing his family's bankruptcy.
