The Public Prosecutor's Office, in any country, is the arm of the law responsible for investigating crimes, gathering evidence and seeing to it that justice is done. In Japan, where collusion among politicians, bureaucrats and business-people is not uncommon, the Public Prosecutor's Office is often the ultimate pillar of moral authority. In addition, Japanese public prosecutors command enormous respect for their professionalism and dedication in the discharge of their duties. This public respect, of course, has been magnified by the consistently high conviction rate they have achieved -- a truth crooked politicians and corrupt bureaucrats alike have learned the hard way once they find themselves the target of an investigation by public prosecutors.

It is, therefore, a sad day when the second-highest-ranking public prosecutor has come under suspicion of possible abuse of office and ethical lapses. Mr. Mamoru Norisada, the superintending prosecutor at the Tokyo High Public Prosecutors Office, has been virtually forced to resign after his name was splashed across the news. Allegedly, Mr. Norisada allowed business associates to pay for entertainment at expensive Ginza hostess bars. There were other reported peccadilloes, such as taking a mistress along on official business trips, registering at a hotel with a woman under a false name and allowing business associates to pay abortion expenses of his mistress.

That Mr. Norisada should resign after all those allegations is not the issue. The Supreme Public Prosecutors Office did the right thing in ordering an investigation as soon as the scandal hit the newsstands (courtesy of a published account by a 28-year-old woman who claimed to have been Mr. Norisada's mistress). Less commendable is the short time the Justice Ministry took in concluding that Mr. Norisada broke no law.