A court on Monday dismissed a damages suit filed by three residents of Fukuoka Prefecture against the state over a diary which the plaintiffs say was tampered with by police to secure the conviction of a man in a bribery case.

The Fukuoka District Court said it is "highly possible that the diary was not forged" by Tokiwa Yamanaka, 67, one of the plaintiffs, but that there was no evidence that investigators had altered it.

Yamanaka was arrested in November 1990 for perjury in connection with a court statement she made in September 1990 supporting her friend, Tsukasa Nishino, 68, who was accused of bribery.

Yamanaka submitted her diary to the court, which said she and Nishino, then an official at a local government institution in charge of sewage disposal, were together in a different place at the time prosecutors said he received money from a sewage disposal company.