The Tokyo District Court found former Liberal Democratic Party heavyweight Kanezo Muraoka not guilty Thursday of concealing a 100 million yen donation from the nation's dental lobby in July 2001 to the then top LDP faction.

Muraoka was accused of playing a key role in illegally concealing the huge unreported donation, which was made by the Japan Dental Association to the LDP's Heisei Kenkyu Kai (Heisei Study Group) in 2001. Muraoka was then acting chairman of the faction, headed by former Prime Minister Ryutaro Hashimoto.

The concealment was revealed in summer 2004, when the faction -- the most powerful in the LDP -- was led by Hashimoto, who, it was widely reported, was the one handed the 100 million yen check.