[1][3] In 2007, Obara was sentenced to life imprisonment on multiple rape charges and manslaughter but was acquitted in the Blackman case for lack of direct evidence.
In December 2008, the Tokyo High Court found Obara guilty on the counts of abduction, dismemberment and disposal of Blackman's body.
[5] During his youth, Obara's father worked his way from a scrap collector to the immensely wealthy owner of a string of properties and pachinko parlors.
[6] After traveling extensively and graduating from Keio University with degrees in politics and law, he became a naturalized Japanese citizen and legally changed his name.
After losing his fortune and his firm during the 1990s recession, Obara was pursued by creditors and reportedly used his business as a money laundering front for the yakuza syndicate Sumiyoshi-kai.
[8] He developed a pattern of criminal behavior, beginning with unlawfully administering drugs to render his victims unconscious, then abducting and raping them.
[10] Police found extensive journals in which Obara made reference to "conquest play",[6] a euphemism describing his sexual assaults on women whom he wrote were “good only for sex" and on whom he sought "revenge on the world"[11] after drugging them with chloroform.
[6][7][12][13] Carita Simone Ridgway (March 3, 1970 – February 29, 1992) was an Australian model from Claremont, Western Australia, who was working in Tokyo's Ginza area as a bar hostess[3] to earn money for acting school.
[17] Blackman had previously worked as a flight attendant for British Airways and went to Japan to see the world and earn money to repay her debts.
[18] As a result of the publicity surrounding the case, three foreign women came forward to describe waking up sore and sick in Obara's bed, with no memory of the night before.
[6] On February 9, 2001, Blackman's body was found in a shallow grave under a bathtub in a seaside cave at Miura, Kanagawa Prefecture, about 50 kilometres (31 mi) south of Tokyo and a few hundred meters from Obara's apartment.
[26] Former prosecutor Takeshi Tsuchimoto criticised the decision to acquit Obara for the murder of Blackman by pointing to the conviction of Masumi Hayashi due to circumstantial evidence.