New Justice Minister Minoru Yanagida said he is confident the Supreme Public Prosecutor's Office will conduct a thorough investigation into the alleged evidence-tampering at the Osaka District Public Prosecutor's Office that led to the arrest of three of its senior ranks.

"I feel the supreme public prosecutors are doing a good job. I will keep monitoring their work and have no intention of intervening," Yanagida said in a group interview Tuesday. Yanagida, a Democratic Party of Japan lawmaker in the Upper House, was appointed justice minister in Prime Minister Naoto Kan's Sept. 17 Cabinet reshuffle.

"I was appointed Friday night and the next Monday I saw newspaper articles about the Osaka prosecutors. I thought, 'why am I facing such a difficult issue from the very start?' "