引發日本財政赤字之政治因素――自「大藏省主導體制」至「首相官邸主導體制」之流變（The Political Analysis of Fiscal Deficit in Japan: From “Ministry of Finance's Control” to “Prime Minister's Office's Control”）

日本の財政赤字の政治的要因―「大蔵省統制」から「首相官邸統制」へ―

本文擬探討政治因素對日本中央公債依存度的變動情況之影響。真淵勝教授主張，造成日本公債依存度在1970年代後期急遽攀升的原因是日本財政部同時是金融政策與財政的主管機構。然而，自1990年代後期，儘管日本著手進行財政和金融分離的制度改革，其中央公債依存度依然急遽攀升，概約而談，這樣的陡升變化似乎不全然可歸結於政治因素。因此，本文欲探討，就法律角度言，從1998年起，理應獨立於政府之外，且長期實施低利率政策的日本銀行，抑或是因自發性判斷而實施長期壓低利息政策的日本銀行，仍可能受到政府‧大藏省（即財務省）施壓，因而輕易地大量發行國債。本文是探討政治因素對於日本的中央公債依存度變動所造成之影響的實證分析。其次，本文也分析在第二次、第三次安倍內閣執政時期，日本銀行遭安倍政府施壓，採取大規模的貨幣寬鬆政策，造成寬鬆的國債發行政策，進而影響財政紀律。總結來說，以政治因素解析日本自1990年代後期以來，大量發行國債的政策，具有合理性。

This article analyzes the change of the ratio of government bond dependency in Japan by political factors. Masaru Mabuchi examined the sharp rise in the rate of government bond dependency in the late 1970s under the influence of political institution, that is, the Ministry of Finance's jurisdiction over both the fiscal policy and the financial administration. However, the ratio of government bond issues to total government expenditures has increased sharply since the late 1990s—when the administrative authorities over fiscal and financial affairs were separated. At a glance, this sharp rise of the ratio cannot be fully attributed to political factors. Nevertheless, this article points that lowering long-term interest rates by the Bank of Japan, which was given legal independence from the government in 1998, has facilitated the large-scale government bond issues. Sometimes the Bank of Japan received pressure from the government and the Ministry of Finance and lowered long-term interest rates; at other times the Bank lowered them on its own initiative. This article also shows that the Prime Minister's office has forced the Bank of Japan to ease monetary policy aggressively during the second and third Abe Administration and that the large-scale monetary easing policy has facilitated large-scale government bond issues and harmed the fiscal discipline. The large-scale government bond issues since the late 1990s can also be attributed to political factors.