A Comparative Study of the Political Systems of the United Kingdom and Japan

As the birthplace of the parliamentary system, the United Kingdom, along with Japana country deeply influenced by the British modelhas provided important references for governance practices around the world. Both countries adopt parliamentary systems and uphold constitutional monarchy, yet they exhibit subtle differences in the relationships among the parliament, the cabinet, and the judiciary. In the UK, the parliament plays a dominant role, with the cabinet deriving its authority from parliamentary power, resulting in a high degree of integration between executive and legislative functions. Under the principle of parliamentary sovereignty, the judiciary exercises limited oversight over the cabinet, leading to a relatively mild system of checks and balances. In contrast, Japan strictly adheres to legal provisions, practicing a clear separation of legislative, executive, and judicial powers through the Diet, the Cabinet, and the courts, respectively. The division and balance of power are more clearly delineated in the Japanese model.