SPRING 2014
FEATURE
Checks and biases
An empirical analysis of polarization in the U.S. Supreme Court
by KEVIN SCHOELZEL ‘14 and SID SAPRU ‘14
E
merging from the landmark
Marbury v. Madison ruling, the
Supreme Court’s power of judicial review represents one of the most
powerful checks on other branches of
American government. Nonetheless,
Supreme Court justices have life tenure,
are not popularly elected, and cannot be
removed outside of a lengthy impeachment process – all important institutional features designed to allow for an unbiased pursuit of justice insulated from
the forces of partisan politics. Given the
tremendous influence of polarization
and political pressures on Congress and
the presidency, however, a thorough examination of the extent to which these
factors affect the Supreme Court is warranted. As such, this article seeks to use
empirical evidence to analyze the degree
to which polarization and political affiliation might have affected the Court
over the last forty years through three
key analyses. First, the overall trend of
polarization is evaluated by examining
the vote margins between the majority and minority opinions of the Court
on a term-by-term basis. Second, these
vote count margins are compared to the
Figure 1
vote count margins that would be expected if Republican-appointed justices
always voted similarly and Democratappointed justices always voted similarly and in opposition to their Republican-appointed counterparts. Lastly,
so-called “landmark” Supreme Court
decisions are examined to det