Two months after the arrest of its chairman stunned Nissan Motor Co. and the entire global automotive industry, the carmaker is weighing abolishing the role altogether as it steps up reforms to rebuild its governance.

Carlos Ghosn's downfall — the auto titan is accused of financial crimes that could put him behind bars for decades — saw Nissan swiftly dismiss him as chairman, leaving the carmaker he once saved from the brink of collapse with a leadership vacuum at the board level. While dispensing with a chairman would raise eyebrows in the U.S. and Europe, Japanese law allows companies to operate without one, with some choosing that route as a way of distributing power across top management.

"We are digging up everything and clarifying and proposing what we can do better to improve governance," Keiko Ihara, 45, one of Nissan's three independent directors, said in an interview in Tokyo. "There is also the debate whether we really need a chairman."