Organ theory of government
In Japanese government in the early twentieth century, the organ theory of government dealt with a fundamental question that arose in Japanese governance: was the abstract state supreme and the Emperor was an "organ" of it, or if the Emperor was not merely the symbol of kokutai and a godlike leader? The "Emperor-Organ" theory is usually considered to have been introduced by Tatsukichi Minobe, a member of the faculty of Tokyo University, and a member of the Diet, during the reign of Emperor Taisho.
While it was not overly controversial when first introduced, it was to have enormous political repercussions in the mid-1930s, in part leading to several coup and assassination attempts.
Introducing the idea
Essentially, Minobe saw the Emperor as the organ of constitutional monarchy. His fellow professor and Diet member, Sakuzo Yoshino advocated a different democratic model, mimpon-shugi. Both incensed members of the Palace and military oligarchies, who did not see Japan as a democracy of any type.
At the time of the death of Mutsohito, the Meiji Emperor, his son, Yoshihito, the weak Taisho Emperor, did not have the ability to carry out Meiji's dual role as ruler and the symbol of legitimacy of his rule. While Hirohito had the strength for both, as seen in many of his Rescripts that contain the term kōso kōsō, "the imperial founders of our House and our other imperial ancestors," which speaks to his authority.
Crisis in 1935
By 1935, Minobe was in the House of Peers, and indeed had lectured to Hirohito and his family. In the previous year, he had speculated about a valid role for political parties, under a "whole nation" Prime Minister of Japan such as Prince Konoe or other aristocrat. He also warned against the oversimplifications of militarism and warned against a staff-officer approach.
The radical militarists objected to Minobe's theory, introduced twenty-seven years before, because it prevented them from exercising absolute authority in the name of the Emperor. Another threat, however, came from Baron Takeo Kikuchi, on 18 February, in the House of Peers, introduced quotes from Minobe, which suggested the Emperor did not transcend the state, comprehend the state, or was more than an organ of the state. Kikuchi accused Minobe, and President of the Privy Council Kita Ikki, of heresy, sacrilege, and lese majeste. He called Minobe a "traitor, rebel and academic bandit."
Minobe, now Dean of Law at Tokyo University, did not, at first, see these as religious issues, and responded, in terms of constitutional law, on 25 February 1935. Unfortunately, popular opinion was not interested in constitutional law, but the role and leadership of the Emperor. Retired major general Geto Genkuro, a Chosu officer purged from the Army in the 1920s, formally charged Minobe with the capital offense of lese majeste. It was later reduced to press code violation, but was in the courts for nine months.
On 4 March, Prime Minister Keisuke Okada said, in the Diet, "No one supports the emperor organ theory." This was to have complex ramifications for his cabinet. While the Diet was in recess, the Okada government asked Minobe to resign and started administrative sanctions against his writing. This had complex ramifications:
In order to counter the unauthorized, radical movement denouncing Minobe's constitutional interpretation, Okada generated a government-sponsored, national kokutai campaign, which also declaimed against Minobe's teachings and banned some of his books and articles. It was this official campaign that Hirohito supported. To control the radicals within the armed forces and resist the kokutai indoctrination movement from below, which aimed at overthrowing Okada, he [Hirohito]lent his authority to a government campaign that fostered unbridled fanaticism.
On 6 April, Inspector General of Military Education General Jinzaburo Mazaki, who was a member of Hiranuma's Kokuhonsha and who provided funds to right-wing newspapers, Mazaki reminded all that the Emperors were living deities. A civilian League to Destroy the Emperor-Organ Theory formed to "accomplish the clarification of the kokutai. League leaders wanted to remake Japan into the image of Nazi Germany, but, in the short term, wanted to remove the influence of Mazaki and Prince Saionji. As the opposition to Okada, the Seiyukai joined with them to help oust the government. 
- Matsuo Takayoshi (1068), Profile of Asian Minded Man (VII), Institute of Developing Economies, Japan External Trade Organization
- Herbert P. Bix (2001), Hirohito and the making of modern Japan, Harper Perennial, ISBN 978-0060931308, pp. 38-39
- Bix, p. 208
- Mikiso Hane (2001), Modern Japan: a historical survey (Third Edition ed.), Westview Press, ISBN 978-0813337562, p. 279
- David Bergamini (1971), Japan's Imperial Conspiracy, Morrow, pp. 590-592
- Bix, pp. 288-289