Carlos Ghosn, chairman of Nissan Motor Co., was arrested in Tokyo on Nov. 19 for underreporting his income and misusing corporate funds to pay for family vacations and properties in four cities around the world.

Some wonder if top Japanese businessmen orchestrated his downfall to prevent Nissan's merger with Renault. The case is also shining an uncomfortable spotlight on the Japanese criminal justice system's reputed presumption of "guilty until proven guilty," with the primary goal of securing a conviction rather than ensuring justice.

The instinctive reaction to the news was: How could he? What was he thinking? Given his massive compensation package (¥5 billion over five years), with an estimated net worth of $100 million, why would he risk imprisonment and the destruction of a lifetime's hard-earned reputation — often voted the world's third or fourth most respected business leader — for another 30 pieces of gold?