Polarization Of The U.S. Supreme Court And Its Causes(1937-2022)

As the highest judicial authority and the ultimate interpreter of the United States Constitution,the U.S.Supreme Court has always prided itself on being "judicially independent",refraining from participating in politics or engaging in partisan disputes.However,against the backdrop of an increasingly divided society and deepening political polarization,the Supreme Court has seen a sharp rise in its 5-4 votes,and the nine Justices have exhibited a high degree of opposition and polarization between liberal Justices and conservative ones.In the voting process,the so-called "swing Justices" of the Supreme Court have all but disappeared;in the court hearings,Justices increasingly play the role of "trial lawyers",infusing their own ideologies and value judgments into the proceedings;and in their daily operations,Justices tend to favor and select law clerks who are ideologically close to themselves.All these signs indicate that polarization between the two major parties in the United States has now extended to the Supreme Court.The high degree of division within the Supreme Court is inevitably connected with the polarization at both the congressional and presidential levels.After all,Justices with lifetime tenure are first nominated by the president and only take office after being approved and confirmed by the Senate.This dissertation argues that it is polarization both at the congressional and presidential levels that has had a profound impact on the nomination system for Supreme Court Justices,ultimately leading to the polarization of the Supreme Court.Specifically,in the presidential nomination process,presidents are increasingly focusing on nominating Justices based on ideology.During the Senate confirmation process,senators are more inclined to support judicial candidates who are ideologically close to themselves and nominated by a president from their own party.Justices nominated and confirmed in this way are more likely to vote consistently with their ideological stance in subsequent decision-making processes,and votes that do not align with the president’s expectations will gradually decrease.In the end,the Supreme Court itself also experiences polarization,and the ideological gap between the two factions of Justices only grows larger and larger.Polarization is undoubtedly one of the most significant features of American political development in recent decades.While there has been extensive research on the polarization of Congress and voters,there has been little discussion on the polarization of the U.S.Supreme Court.In the context of polarization,Supreme Court Justices who are nominated by the President and approved by Congress are inevitably a product of polarization.Serious studies of polarization in contemporary America cannot ignore the Supreme Court in the "separation of powers" system,while the study of the current U.S.Supreme Court cannot be divorced from the context of polarization.Therefore,this doctoral thesis aims to fill the research gap by comprehensively and systematically studying the nomination of Supreme Court Justices,from the presidential nomination stage,Senate approval stage,to the Justices taking-office stage.From the perspective of polarization,this thesis provides a new viewpoint for the research of the Supreme Court Justices nomination system.Meanwhile,this research examines the phenomenon of American polarization from the perspective of the judicial branch in the"separation of powers" system,hoping to gain a more comprehensive understanding of American political polarization in and of itself.Finally,in contrast to domestic scholars’ largely qualitative analysis of the Supreme Court Justices nomination system,this dissertation combines and employs various quantitative methods to empirically examine the impact of polarization on the U.S.Supreme Court,constituting a valuable attempt to use empirical analysis to study the U.S.Supreme Court.