The Supreme Public Prosecutors Office on July 8 announced reform of the special investigation squads, which exist at the district public prosecutors offices in Tokyo, Osaka and Nagoya. The reform was prompted by recent irregular events involving investigators of such squads, which have contributed to deepening people's distrust of the nation's prosecution system.

A prosecutor of the Osaka squad was found to have tampered with evidence in a case in which Ms. Atsuko Muraki, a former health and welfare ministry official, was indicted on a charge of forging an official document and was eventually acquitted in September 2010.

On June 30, 2011, the Tokyo District Court decided not to use the core part of an investigator's records of oral statements by a former secretary of former Democratic Party of Japan chief Ichiro Ozawa in a trial over alleged bookkeeping irregularities by Mr. Ozawa's fund management body. The court said that an investigator used threats and leading questions to obtain the testimony he wanted.