On May 28, 2007, Japan’s Minister of Agriculture, Toshikatsu Matsuoka, hanged himself in his residence. Accused of corruption and about to face an inquiry in Parliament, Mr. Matsuoka committed suicide. Were the accusations related to the power that his position conveyed? Mr. Matsuoka was facing corruption charges brought about by undeclared political donations.

Does the Ministry of Agriculture, with ample scope for patronage, afford the same value to a political actor as more prestigious posts in Ministry of Foreign Relations or Ministry of Justice? Is the number of cabinet posts different political factions hold an accurate measure of their weight within a government? In “Ministerial Weights and Government Formation,” Taka Adachi (University of Pennsylvania) and Yas Watanabe, from the Kellogg School’s Management and Strategy Department, analyze Japan between 1958 and 1993 to illustrate that potential ministers may ascribe different weights to different posts in the cabinet; they also explain how ministerial seats are assigned.

How does the Japanese parliamentary system work? Is there something particular in the Japanese version? Similar to other major democracies, the Japanese legislature, the National Diet, is composed of two chambers that elect the Prime Minister. If the two disagree, the more powerful House of Representatives bears the tasks of making the final decision. As head of the cabinet, the Prime Minister appoints every minister. The only restriction in this process is that the majority of the appointees must be legislators. Once the cabinet is formed, the Emperor formally appoints the Prime Minister.

What is particular to the Japanese case is that since the 1950s the main party, the Liberal Democratic Party (LDP), has held almost uninterrupted power and has always held the majority in the House of Representatives. Moreover, the Prime Ministers were always LDP presidents. In Japan, there is a strong sense of party discipline. None of the factions in the LDP has ever attempted to pass a resolution of no confidence after cabinet formation (except once in 1980 and not related to cabinet formation), and no faction split from the LDP during the period analyzed by Adachi and Watanabe. These facts suggest convergence among the different factions on various policy issues. In fact, party factions play a major role in cabinet formation, and any faction with a significant representation in Parliament will occupy cabinet posts. Adachi and Watanabe’s findings for Japan between 1958 and 1993 are clear: the bargaining power of the factions is fully explained by the number of seats each holds in Parliament and the Prime Minister’s political identification with a faction.

What is the procedure for forming the cabinet function? In the first place, the Prime Minister advances an offer to every faction. These factions can agree or they can demand changes in the number of the seats and the allocation of ministers. If a faction still disagrees with the revised proposal, it may demand the re-assignation of the party president, issue a vote of no confidence, or simply split from the party. This situation did not arise during the period considered. Consequently, Adachi and Watanabe conclude that all the factions unanimously agreed with the cabinet formation process. If the contrary were true, some factions would have held a considerable number of seats in the Diet but lack cabinet posts.

By using a formal structural model to show this specific bargaining between the political actors and econometric techniques, the authors explain how the ministerial seats are assigned in Japan. More broadly, they provide a framework to answer several relevant questions for understanding the internal politics of parliamentary democracy. Following this strategy, they provide very interesting results on the assignation of cabinet posts, the formateur advantage, and novel estimations of the value or weight of those ministries.

Adachi and Watanabe show that simply counting cabinet posts does not give an accurate measure of each faction’s power. To do so, they use observable data about the number of seats the LDP had in the House of Representatives, the number of seats each faction held at the time of cabinet formation, the allocation of cabinet posts to each faction, and the identity of the Prime Minister’s faction. During the period they analyze, forty-four cabinets were formed and the number of factions within the LDP varied between five and twelve. Table 1 below illustrates some of their results regarding the estimated relative weights of the ministries. For example, the relative importance of being the Prime Minister with respect to being in charge of the Foreign Affairs Ministry is almost nine times greater. However, the Ministry of Construction, which weighs almost as much as the Ministry of Finance, weighs twice as much as the Ministry of Foreign Affairs.

Table 1: Relative weights of selected ministries

Prime   MinisterConstructionAgricultureFinanceForeign   Affairs
Prime Minister14.45.36.89.4
Construction11.21.32
Agriculture11.11.8
Finance11.6
Foreign Affairs1

Adachi and Watanabe also find that the power garnered by the Prime Minister’s faction is more than proportional to the fraction of seats it holds in the Diet—this is the formateur’s  advantage.

The interpretation of the results is very straightforward and intuitive: politicians are mostly pork-barrel oriented and ascribe a larger weight to ministries where the budget allows more opportunities for political patronage. In other words, they prefer being appointed to the Ministry of Construction, Agriculture, Transport, or Defense (where the budget is bigger) rather than to Foreign Affairs or Justice, where the value of the office relies more on reputation and seniority. These cabinet posts are determined by the influence of a political faction in the Diet; specifically, the formateur’s advantage and the number of seats are of great significance.

Toshikatsu Matsuoka held a desirable cabinet post in which pork-barrel attributions were pivotal. The power conveyed in occupying cabinet posts such as the Minister of Agriculture or of Defense facilitates abuses and corruption. For Toshikatsu Matsuoka, the almost certain possibility of being sentenced for dishonesty while occupying a public position was probably just too much to bear.