TOKYO - A JAPANESE court will rule on Tuesday whether a serial rapist abducted and killed British bar hostess Lucie Blackman after he was controversially earlier acquitted over her death.

Ms Blackman's slaying in 2000 triggered a storm of media coverage in Britain and even a personal appeal by its then prime minister Tony Blair to find her killer.

The suspect in the spotlight is Joji Obara, 56, a wealthy former property developer in Tokyo, who was sentenced in April last year to life in prison for raping nine women including one who died, Australian Carita Ridgway.

Both sides have appealed the case to the Tokyo High Court - Obara wants to clear his name over the deaths of both Ms Blackman and Ms Ridgway and wants lesser punishments for the rapes.

Prosecutors, however, are seeking his conviction in Ms Blackman's death.

Obara's acquittal by the district court in the Blackman case was especially surprising as nearly 99 per cent of people brought to trial in Japan are convicted - a rate that has alarmed human rights groups and legal experts.

Japanese prosecutors generally drop cases when they believe there is insufficient evidence.

Obara has not been charged with first-degree murder, which would have made him eligible for the death penalty.

Ms Blackman vanished in July 2000 while she was working in bars in Tokyo's seedy Roppongi district to save money for a holiday in Australia.

Her dismembered body was found seven months later in a seaside cave.

The district court had ruled that Obara, who has denied all charges, was responsible for Ms Ridgway's death by giving her chloroform, a colourless drug used as an anaesthetic in the 19th century.

Defence lawyers have said chloroform was not detected in Ms Blackman's body.

In an appeal hearing in May, a professor who testified on behalf of the prosecutors said it was normal that the drug was not detected in a body that had been abandoned for more than six months.

The Tokyo High Court decision comes against a background of a lack of leads in another high-profile case in Japan concerning a young Briton, a 22-year-old English language teacher, Ms Lindsay Ann Hawker, who was found dead in a bathtub last year.

Police are still loking for the prime suspect, Tatsuya Ichihashi, who fled from officers when they visited his apartment in suburban Tokyo where Ms Hawker's body was found. -- AFP