The family is seeking 150 million yen from top boss Shinobu Tsukasa, who is also known as Kenichi Shinoda, number-two boss Kiyoshi Takayama, and three others for compensation over a fire set inside hostess club Infinity on September 3, 2010.
Three people received serious burns in the attack, with 27-year-old Masasa Sano eventually succumbing to his injuries.
Two members of the Yamaguchi-gumi, Mitsutoshi Matamura (36) and Osamusho Ikemoto (48), were later found guilty on murder and arson charges and received sentences of 30 years and life in prison, respectively.
“By only bringing the perpetrators to justice does not prevent the recurrence of further damage by organized crime,” said the lawyer for the bereaved family at a press conference.
The attack was related to a refusal by the club to pay protection money to the Kodo-kai, an affiliate group of the Yamaguchi-gumi whose top boss is Takayama. The year before, the owner of the club’s parent company was assaulted, whereby he received serious injuries.
Revisions made to the Anti-Organized Crime Law in 2008 allow civilians to seek damages from gang members for harmful incidents in civil court. According to police, in the eight cases raised since the amendment, gang members paid out compensation four times.