
Junji Sugiuchi (1961-10 March 2010) was a Japanese yakuza criminal and a homicide detective for the Tokyo Metropolitan Police Department (TMPD). He infiltrated the police on behalf of the Uenoseiwa-kai during the 1980s, and he served as Isao Katsuragi's "inside man" and as TMPD deputy commissioner Seishiro Munakata's private assassin until he was murdered on Munakata's orders in 2010 to prevent his arrest and interrogation.
Biography[]

Sugiuchi in 1985
Junji Sugiuchi was born in Tokyo, Japan in 1961, and he joined the Uenoseiwa-kai yakuza clan at a young age. He became oath brothers to Isao Katsuragi before being assigned to join the Tokyo Metropolitan Police Department in the early 1980s, serving as a spy for the Ueno Seiwa. He was assigned to the Homicide Division, in which capacity he helped plot the Tojo-kai's "Ueno Seiwa hit" of 1985 to help bring about Katsuragi's rise in the ranks of that clan. He provided Taiga Saejima with a gun containing police-issued rubber bullets (unbeknownst to Saejima) through Kazuo Shibata and Goro Majima, and, after Saejima incapacitated his targets on 21 April 1985, Katsuragi executed the unconscious henchmen before having Sugiuchi shoot him in the shoulder to make it appear as if he was injured while defending his boss Yoshiharu Ueno. Sugiuchi proceeded to falsify the police report to declare that Saejima was the killer and had acted alone, but his superior Seishiro Munakata confronted Sugiuchi about the irregularities and offered to let the report stand as written only if Sugiuchi introduced him to Katsuragi. Munakata would subsequently blackmail Katsuragi, Shibata, and Sugiuchi over their roles in the Ueno Seiwa massacre, and he also forced Sugiuchi to murder his partner Taigi Tanimura after the latter discovered the conspiracy. Sugiuchi became Munakata's personal hitman, all while maintaining a respectable, if merciless reputation among his colleagues.

Sugiuchi's death
In March 2010, Munakata had Sugiuchi warn Shun Akiyama and Taigi's son Masayoshi Tanimura to maintain a distance from the brewing conflict between the Ueno Seiwa and Tojo clans, which was engineered by Munakata to bring about Hiroaki Arai's rise to power. Sugiuchi developed a particular rivalry with Akiyama, placing him under 24-hour police surveillance, ostensibly to protect him from the Shibata-gumi, but truly to prevent him from contacting Arai. When Tanimura discovered that Sugiuchi was partnered with his father in 1985, he decided to lure him into a trap by reporting his meeting with Yutaka Mishima at the Tokyo docks on the night of 10 March 2010. Sure enough, Sugiuchi showed up and killed Mishima, only for Junichi Sudo and the TMPD to arrive and attempt to arrest Sugiuchi. Sugiuchi reminded the police that they were not allowed to use their guns, and he proceeded to flee on a motorboat, causing Tanimura to give chase. Ultimately, Tanimura shot out Sugiuchi's engine and forced him to return to shore, where Sugiuchi resisted arrest and was eventually beaten down. Defeated, Sugiuchi confessed his remorse for Taigi Tanimura's murder and for the undeserved praise that he had accrued as a policeman. He then said that meeting Masayoshi made him wish that he had gone straight years before, and he proceeded to offer his surrender. Just then, however, he was fatally shot by Satoshi Hisai, who had been sent by Munakata to eliminate Sugiuchi before he could be captured. Sugiuchi died in Tanimura's arms, erasing a potential lead in Tanimura's investigation of police corruption.