The Different Manifestations of Representative Drift on U.S. State and Federal Courts.
Justine D'Elia
Stony Brook University
Jeffrey A. Segal
SUNY Distinguished Professor
Stony Brook University
We presented an earlier version of this paper at the Oxford University Conference on “Courts as
Representative Institutions,” Wolfson College, Oxford, October 19, 2012.
The Different Manifestations of Representative Drift on U.S. State and Federal Courts
Introduction: The Importance of Normative Implications for Empirical Research
One of the complaints of those in the Perestroika movement is that quantitative scholars
all too frequently ignore important normative issues (Miller 2001). Indeed, in urging a
normative focus to our work, Graber (2006) wrote that “political science scholarship is valuable
only to the extent that works help citizens and policymakers make better political decisions (p.
4).” Our view is that political science scholarship is valuable to the extent that works help
students and scholars better understand the political world. Knowledge is our primary goal; it is
an end in and of itself. Nevertheless, we also argue that the quantitative empirical research
Perestroikans criticize often has as much if not more to say about normative questions than
explicitly normative research does.
Consider the death penalty. Normative theorists can make argument after argument
about why the death penalty is moral, immoral, whatever, but in the end these arguments are
largely justifications for pre-existing views and do little to change most people’s minds.
Empirical theorists, by contrast, may actually provide information that is more valuable
to the normative debate than normative theorists do. Imagine a world in which capital
punishment had a coarsening effect on society, so much so that each additional execution led to
five more people being murdered (Thomson 1997). It would be difficult to imagine that even the
strongest supporters of the death penalty would continue to support it if each execution of a
murderer resulted, on average, in five new murder victims. Alternatively, what if in fact there is,
as Sunstein and Vermeule (2006) suggest, a deterrent effect to capital punishment that is
“powerful” and “impressive” (p. 706)? What if, for every legally guilty person executed, two
1
innocent lives were spared through deterrence? Or four? Or eight, as Isaac Ehrlich (1975)
argues. Is there some point at which opponents of the death penalty change their minds in
response to a large and demonstrated deterrent effect?
Empirical arguments may be crucial for normative debates over affirmative action too.
Consider longstanding arguments about the merits of affirmative action. To no one’s surprise,
most of the supporters come from left of center while most of the opponents come from right of
center. But as interesting and as intelligent as these debates have been, they rarely push people
from their pre-existing positions. Missing from the normative debate, though, has been any
evidence about the empirical effects of affirmative action. What if Rick Sander and Stuart
Taylor (2012) are correct? What if affirmative action in law schools actually leads to fewer
African Americans becoming lawyers (see also Sander 2004; for a critique Wilkins 2005)? Or
doctors? Would not this empirical work have far greater normative consequences than most of
the normative writings on the subject?
This paper applies this view about the normative implications of empirical questions to
the study of federal versus state judicial selection mechanisms and the extent to which they result
in different levels of ideological drift among the judges. Given the nature of the appointment
processes of judges in the United States, federal judges represent the dominant political coalition
in power at the time of the judge’s appointment, whereas state judges frequently represent the
voters of their states. They are not representatives in the “delegate” sense of the term but rather
in the “trustee” sense. They do not owe anyone specific rulings on anything, but rather, their
judgment on the legal issue at hand. Because few important judicial questions have a right
answer, but rather, are contestable, those who appoint judges typically try to appoint those who
share their ideological values, hoping or expecting that the judgments that result will reflect
2
those values. Even in this sense, though, judges are not very reliable representatives. In the
federal case, judges usually begin their tenures close to the positions of those who appointed
them. Nevertheless, there is a marked tendency for judges to drift ideologically from the views
they were known for prior to their court tenure. In the state case, the representative function
works in a cyclical fashion: judges become more representative of their constituents the closer
they are to re-election or reappointment. We systematically examine representative drift on the
U.S. Supreme Court, using data derived from the U.S. Supreme Court Data Base (Spaeth,
Epstein, Martin Ruger, and Segal, 2012). While we do not have original data on state court
decisions; we nevertheless analyze counter drift by state court judges through a review of various
relevant studies.
Ideological Drift on Federal Courts
The assumption that Supreme Court justices have stable preferences over the course of
their careers is a ubiquitous feature of much of the existing literature on the court. Although
neither of the two major models of Supreme Court decision making, the attitudinal model or the
rational choice model, explicitly make this assumption the modeling choices researchers make
when testing these models often do (Epstein et al.1998). While numerous scholars have
unquestionably accepted this assumption as valid, recent scholarship has called this practice into
question (Epstein et al. 1998; Epstein et al. 2007).
Testing for Ideological Drift on the Federal Courts
One way to assess the extent of ideological drift among Supreme Court justices is to
contrast how well their ideology at the time of their appointment predicts their behavior in their
3
first few terms compared to how well it predicts their behavior after a more extended time on the
bench. If the justices do systematically drift ideologically then we would expect that their
ideology at the time of their appointment to explain their behavior better during the first four
years than it does after ten years or more. On the other hand, if ideological drift does not occur
systematically then ideology should explain the justices’ behavior equally well regardless of how
many years have passed since their appointment. Following Epstein et al. (2008) we use the
justices’ Segal-Cover (Segal and Cover 1989) scores as a measure of their ideology at the time of
their appointment and consider only justices who have severed ten years or more on the Court.
We measure the justices’ behavior, using the U.S. Supreme Court Data Base (Spaeth et al. 2012)
as the percent of all cases they decided liberally. We run two separate but identical regressions
using the Segal-Cover scores to explain judicial behavior in the first four years of a justice’s term
and in terms occurring ten years or more after the justice’s appointment to the Court. The results,
presented in Table One, demonstrate the drop in measures of fit is striking: in the first four years
of a justice’s career Segal-Cover scores can explain about 64 percent of the variation in their
voting behavior. After ten years of service, however, Segal-Cover scores explain only 45 percent
of this variation. Moreover, the root mean squared error increases from 8.47 to 12.12.1
Note that as Rehnquist’s ideology score was calculated separately for his appointment as associate justice
(Rehnquist 1) and chief justice (Rehnquist 2), he enters our model twice. This is essential in our next model, where
Rehnquist’s two appointing presidents had different ideologies. Here, the split works against our hypothesis as it
gives Rehnquist a new baseline as of the 1986 Term.
1
4
Table 1: Explaining Judicial Behavior with Ideology
First Four Terms
Terms After Ten Years
Ideology Coefficient
Standard Error
16.43***
(3.00)
15.89***
(4.29)
N
Adjusted R Squared
Root MSE
19
0.64
8.47
19
0.45
12.12
*** Significant at the .000 level for a one tailed test
Figure 1
5
Figure 2
The fact that the justices’ ideology at the time of their appointment explains their
behavior better in the first four years of their term then in terms after ten years provides evidence
that ideological drift does occur over time. Using a similar test we can also asses if the justices’
ideology drifts from the ideology of the president who appointed them. Assuming that presidents
want to appoint Supreme Court justices who reflect their own ideology (Epstein et al. 2007) we
can use the appointing president’s Common Space Score (Carroll, Lewis, Lo, McCarty, Poole,
6
and Rosenthal (2011) to explain judicial behavior. If the justices do not drift ideologically then
we would expect the president’s Common Space score to explain judicial behavior equally well
in the first four years of a justice’s term compared to terms after ten years. This would indicate
that presidents can leave a lasting impact on the Court. If on the other hand, Presidential
Common Space scores are a worse predictor of judicial behavior after a justice has been on the
Court for over ten years then this would indicate that the justices drift ideologically and the
president’s ideological imprint on the Court may be more fleeting than is often assumed.
To test for these effects we again run two separate regressions on judicial behavior one
on the first four terms and one after ten years of service. We use both the nominating president’s
Common Space score and the median Common Space Score for the Senate to explain judicial
behavior. The median Senate score is included to account for the possibility that the president
has to strategically select nominees who can get Senate approval (Moraski and Saipan 1999).
The results presented in Table Two show that in the first model examining only a justice’s first
four terms the nominating president’s common space score is a significant predictor of the
justices’ behavior. In the second model examining terms after ten years of service the president’s
common space score remains significant, but just barely so. The Senate median is not significant
in either model.2 Perhaps more important, however, is the drop in the adjusted R squared
between the first model from 0.38 to 0.14 in the second.3 This indicates the first model explains
substantially more variation in the behavior of the justices than does the second. The RMSE also
indicates that the first model is a better fit, because it increases from a 10.8 to a 14.7 from the
2
Using the mean Common Space for the Senate instead of the median does not change the results.
Some but not all of the drop in the adjusted R squared can be attributed to the decreased explanatory power of the
median common space score for the Senate. When the models are reran with the inclusion of this variable the
adjusted R squared drops from .42 to .23.
3
7
first model to the second. Together these results provide compelling evidence that the justices’
ideology does, over time, drift from the ideology of the president who appointed them.
Table 2: Explaining Judicial Behavior with the President’s Ideology
First Four Terms
Terms After Ten Years
President’s CSS
Standard Error
-25.72**
(7.19)
-20.62*
(9.78)
Median Senate CSS
Standard Error
28.76
(31.00)
5.36
(42.20)
N
Adjusted R Squared
Root MSE
19
0.38
10.80
19
0.14
14.70
** Significant at the .01 level for a one tailed test; * Significant at the .05 level for a one tailed test.
Figure 3
8
Figure 4
Ideological Drift and in State Courts
Justices at the federal level may not be reliable representatives, because of their tendency
to drift ideologically from the views they expressed at the time of their appointment. Thus once
appointed, federal justices are only representative in the “trustee sense” and cannot be expected
to directly represent the views of the people. Several studies, however, have found that state
court justices drift in a different manner (Hall 1987; Hall 1992; Brace and Hall 1995; Traut and
Emmert 1998; Caldarone, Canes-Wrone and Clark 2004; Savchak and Barghothi 2007; Brace
and Boyea 2008). State court justices thus are much more likely to issue rulings more directly
reflective of the voice of the people, at least as elections approach. These findings extend across
9
many issues. The most prominent of which is the issue of the death penalty (Hall 1992; Brace
and Hall 1995; Traut and Emmert 1998; Brace and Boyea 2008). Hall (1992) finds that justices
in states that are highly supportive of the death penalty are more likely to uphold sentences when
they are more electorally vulnerable, even if this is inconsistent with their true preferences. Brace
and Boyea (2008) likewise find that state level public opinion on the death penalty influences the
decisions of elected state judges. In a similar study looking at abortion cases, Caldarone, CanesWrone, and Clark (2004) find that the public’s level of support or opposition to abortion
influences state justices when issuing decisions in these cases. Additionally, state liberalism has
been found to influence the number of decisions that are supportive of defendant rights in
criminal cases (Savchak and Borghothi 2007). Moreover, given the fact that the public
overwhelmingly believes that local judges are not harsh enough on criminals (Epstein, Segal,
Spaeth, and Walker (2012, table 8-7), it is no surprise that trial judges become significantly
harsher in criminal sentencing decisions as their reelection nears (Huber and Gordon 2004).
Combined these studies offer compelling evidence that state court justices may in fact
drift from the ideology of the people they represent, but over time they move back in line.
Federal judges as we have seen, however, do have the propensity to drift ideologically over time.
This raises the question of why. Recent studies have pinpointed electoral competition as the main
causal mechanism behind this discrepancy (Hall 1992; Brace and Hall 1995; Hall 2012), with a
wealth of studies documenting the way in which elections constrain justices from drifting too far
from the people (Hall 1992; Brace and Hall 1995; Hall 2012). Both anecdotal and empirical
evidence support the idea that justices actively worry about how the decisions they make will be
perceived by their constituents (Hall 1987; Drechsel 1987). Hall (1987) finds that justices
sometimes repress dissents because of electoral considerations, and this effect is magnified for
10
risk adverse justices (Brace and Hall 1990). Meanwhile, Drechsel (1987) finds that elected
judges are more likely to monitor information about themselves and public reactions to their
decisions in the media. Hall (2012), however, presents perhaps the best empirical test of this
theory by comparing the behavior of state justices who are prohibited from serving another term
due either to mandatory retirement ages or term limits with the behavior of justices who are free
to seek an additional term. She finds that justices who are prohibited from running again are
more likely to cast unpopular votes on death penalty cases. This suggests that, absent electoral
pressure, state court justices may behave in a manner more consistent with federal court justices.
In the rare instances in which state court justices, despite having to run for election, do
act more like federal justices and drift ideologically over time this disconnect is quickly
corrected. Justices who persist in voting out of sync with their constituents on death penalty
cases are more likely to be defeated in subsequent elections (Traut and Emmert 1998). This may
partly be a result of the fact that voting against the public in death penalty cases is associated
with a greater chance of facing a quality challenger in the next election (Brace and Boyea 2008).
Defeat, however, is not the only mechanism by which these imbalances are corrected. Justices
are more likely to voluntarily retire if they anticipate a close election as a result of a population
that has shifted ideologically away from them Hall (2001). This stands in stark contrast to the
federal case where justices can drift ideologically without impunity until death do they depart.
Policy Implications
The different types of representation offered by federal court justices and state court
justices have many practical implications for the direction of policy in the United States. State
court justices are more representative in the “delegate” sense of the term, and consequently, their
11
decisions are more likely to be influenced by the opinion of the people (Hall 1987; Hall 1992;
Brace and Hall 1995; Traut and Emmert 1998; Caldarone, Canes-Wrone and Clark 2004;
Savchak and Barghothi 2007; Brace and Boyea 2008). If this type of representation is the goal
then fixed terms for federal court judges and shorter terms for state court justices may be in
order. For federal justices, Epstein et al. (2008) theorize that ideological drift may not be a major
concern until after a justice has served for ten terms or longer. These results indicate that
implementing term limits for federal judges may obviate the effects of ideological drift. For
example, an eighteen year term limit for Supreme Court justices would give presidents two
appointments every term, and might lessen the vitriolic confirmation battles that have taken place
since the Bork nomination in 1987 (see Epstein and Segal 2005). As for state court justices there
is substantial evidence that suggests that shorter terms are likely to increase “delegate” style
representation, because judges are more influenced by the public when their upcoming election
looms closer (Hall 1992; Hall and Brace 1995; Savchak and Borghothi 2007). These reforms are
likely to work if increasing “delegate” style representation is the goal.
If, on the other hand, judicial independence is valued then perhaps “trustee”
representation is to be preferred over “delegate” representation and steps should be taken insulate
justices from the effects of public opinion. This would give them the freedom to make unpopular
decisions that are, nonetheless, consistent with the law. This may be particularly important in
cases that deal with the rights of minorities. Vines (1965), for example, in an examination of how
state supreme courts decided race relations cases found that of the southern states, both Virginia
and South Carolina, the only two southern states who used the legislature to selective to their
judges instead of popular election, had good records of deciding cases in favor of blacks
compared to most of the other southern states. Thus both “delegate” and “trustee” representation
12
can be important and perhaps the best judicial system would be one that finds a way to
adequately balance these two different competing conceptions of representation.
13
References
Brace, Paul, and Brent D. Boyea. 2008. “State Public Opinion, the Death Penalty, and the
Practice of Electing Judges.” American Journal of Political Science 52 (2): 360372.
Brace, Paul and Melinda Gann Hall. 1990. “Neo-Institutionalism and Dissent in State
Supreme Courts.” Journal of Politics 52 (1): 54-70.
Brace, Paul, and Melinda Gann Hall. 1995. “Studying Courts Comparatively: The View
from the American States.” Political Research Quarterly 48 (1): 5-29.
Baum, Lawrence and Neal Devins. 2010. “Why the Supreme Court Cares About Elites, Not the
American People.” College of William and Mary Law School Scholarship Repository 58
(Faculty Publications Paper 1116): 1515-1581.
Braman, Eileen 2006. “Reasoning on the Threshold: Testing the Separability of Preferences in
Legal Decision-Making.” Journal of Politics 68 (2): 308-321.
Caldarone, Richard P. and Brandice Canes-Wrone, and Tom S. Clark. 2009. “Partisan Labels
and Democratic Accountability: An Analysis of State Supreme Court Abortion
Decisions.” The Journal of Politics 71 (2): 560-573.
Canon, Bradley C. 1973. “Is the Exclusionary Rule in Failing Health? Kentucky Law Journal 62:
681-730.
Carroll, Royce, Jeff Lewis, James Lo, Nolan McCarty, Keith Poole, and Howard Rosenthal.
2011. “Common Space” DW-Nominate Scores with Bootstrapped Standard Errors.
Available at http://voteview.com/index.asp.
Drechsel, Robert E. 1987. “Accountability, Representation and the Communication
Behavior of Trial Judges.” The Western Political Quarterly 40 (4): 685-702.
14
Ehrlich, Issac. 1975. “The Deterrent Effect of Capital Punishment: A Matter of Life and Death.”
The American Economic Review 65(3): 397-417.
Epstein, Lee and Andrew D. Martin, Kevin M. Quinn, and Jeffrey A. Segal. 2007. “Ideological
Drift Among Supreme Court Justices: Who, When, and How Important?” Northwestern
University School of Law 101 (4): 1483-1542.
Epstein, Lee and Jeffrey A. Segal. 2005. Advice and Consent: The Politics of Judicial
Appointments. New York: Oxford University Press.
Epstein, Lee and Jeffery A. Segal, Harold J. Spaeth, T. G. Walker. 2012. Supreme Court
Compendium 5th Ed. Washington D.C.: C.Q. Press.
Epstein, Lee and Valerie Hoekstra, Jeffrey A. Segal, and Harold J. Spaeth. 1998. “Do Political
Preferences Change? A Longitudinal Study of U.S. Supreme Court Justices.” The Journal
of Politics 60 (3): 801-818.
Flemming, Roy B. and Dan Wood. 1997. “The Public and the Supreme Court: Individual Justice
Responsiveness to American Policy Moods.” American Journal of Political Science 41
(2): 468-498.
Graber, Mark A. 2006. “A Letter from the Section Chair: Perestroika and Public Law” Law &
Courts Newsletter of the Law & Courts Section of the American Political Science
Association 16 (3): 1, 4-5.
Hall, Melinda Gann. 1987. “Constituent Influence in State Supreme Courts: Conceptual
Notes and a Case Study.” The Journal of Politics 49 (4): 1117-1124.
Hall, Melinda Gann. 1992. “Electoral Politics and Strategic Voting in State Supreme
Courts.” The Journal of Politics 52 (2): 437-446.
Hall, Melinda Gann. 2001. “Voluntary Retirements from State Supreme Courts:
15
Assessing Democratic Pressures to Relinquish the Bench. The Journal of Politics
63 (4): 1112-1140.
Hall, Melinda Gann. 2012. “Representation in State Supreme Courts: Evidence From the
Terminal Term.” Paper delivered at the 2012 State Politics and Policy Conference.
Huber, Gregory A. and Sanford C. Gordon. 2004. “Accountability and Coercion: Is Justice Blind
When It Runs for Office.” American Journal of Political Science 48 (2): 247-263.
Lord, Charles Marc Ross and Mark Lepper. 1979. “Biased Assimilation and Attitude
Polarization: The Effects of Prior Theories on Subsequently Considered Evidence.”
Journal of Social Psychology 37 (11): 2098-2109.
Kahan, Dan M. and Donald Braman. 2003. “More Statistics, Less Persuasion: A Cultural Theory
of Gun-Risk Perceptions.” University of Pennsylvania Law Review 151 (4): 1291-1327.
Lodge, Milton and Charles S. Taber. 2013. The Rationalizing Voter. Cambridge: Cambridge
University Press.
Miller, D.W. 2001. “Storming the Palace in Political Science.” The Chronicle of Higher
Education.
Moraski, Bryon J. and Charles R. Shipan. 1999. “The Politics of Supreme Court Nominations: A
Theory of Institutional Constraints and Choices.” American Journal of Political Science
43 (4): 1069-1095.
Owens, Ryan J. and Justin Wedeking. 2012. “Predicting Drift on Politically Insulated
Institutions: A Study of Ideological Drift on the United States Supreme Court.” The
Journal of Politics 74 (2): 487-500.
Sander, Richard H. 2004. “A Systemic Analysis of Affirmative Action in American Law
School.” Sand. Law Review 57: 367-483.
16
Sander, Richard H. and Stuart Taylor 2012. Mismatch: How Affirmative Action Hurts Students
It’s Intended to Help and Why Universities Won’t Admit It. New York: Basic Books.
Savchak, Elisha Carol and A. J. Barghothi. 2007. “The Influence of Appointment and Retention
Constituencies: Testing Strategies of Judicial Decisionmaking. State Politics and Policy
Quarterly 7 (4): 394-415.
Segal, Jeffrey A. and Albert D. Cover. 1989. “Ideological Values and the Votes of Supreme
Court Justices.” American Political Science Review 83 (2): 557-565.
Segal, Jeffrey A. 2007. “Normative Implications of Empirical Theory.” Law and Courts 17 (1):
1, 4-5).
Spaeth, Harold and Lee Epstein, Ted Ruger, Keith Whittington, Jeffrey Segal, Andrew D.
Martin. 2012. The Supreme Court Database. Available at http://scdb.wustl.edu/
index.php.
Sunstein, Cass R. and Adrian Vermeule. 2006. “Is Capital Punishment Morally Required? Acts,
Omissions, and Life Traders.” Stanford Law Review 53: 703-750.
Taber, Charles S. and Milton Lodge 2006. “Motivated Skepticism in Evaluation of Political
Beliefs.” American Journal of Political Science 50 (3): 755-769.
Thomson, Ernie. 1997. “Deterrence Versus Brutalization: The Case of Arizona.” Homicide
Studies 1 (2): 110-128.
Traut, Carol Ann, and Craig F. Emmert. 1998. “Expanding the Integrated Model of
Judicial Decision Making: The California Justices and Capital Punishment.” The
Journal of Politics 60 (4): 1166-1180.
Vines, Kenneth N. 1965. “Southern State Supreme Courts and Race Relations.” The Western
Political Quarterly 18 (1): 5-18.
17
Wilkins, David B. 2005. “A Systematic Response to Systematic Disadvantage.” Stand. Law
Review 57: 1915-1961.
18