One of the more intriguing questions stemming from the Toshiba accounting scandal is this: Where was the whistleblower?

Top executives at the industrial conglomerate, which makes everything from refrigerators to nuclear reactors, padded pretax profit by at least ¥152 billion over six years, according to a third-party accounting probe.

The review by accountants and lawyers, led by a former investigator with the Tokyo District Public Prosecutor's Office, cited "institutional" accounting malpractices and a corporate culture "where it was impossible to go against the boss's will."