Segal–Cover score explained

A Segal–Cover score is an attempt to measure the "perceived qualifications and ideology" of nominees to the United States Supreme Court. The scores are created by analyzing pre-confirmation newspaper editorials regarding the nominations from The New York Times, Washington Post, Chicago Tribune, Los Angeles Times, St. Louis Post-Dispatch, and The Wall Street Journal. Each nominee receives two scores that range from 0 to 1 based on the average score of all articles from these sources:

The Segal–Cover scoring was introduced by Jeffrey Segal and Albert Cover (both of Stony Brook University) in their 1989 article "Ideological Values and the Votes of U.S. Supreme Court Justices".[2] [3] The scores have since been updated as part of The Supreme Court Justices Database, a project led by USC Gould School of Law Professor Lee Epstein. The updated scores cover all nominees from Hugo Black in 1937 to Amy Coney Barrett in 2022.[4] A score for Kentanji Brown Jackson has not yet been published.

Because the scores are based on perceptions before the nominee takes a seat on the Court, they provide a measure of the ideological values of Supreme Court justices that is independent of the votes they later cast.

Scores

The Segal–Cover perceived qualifications and ideology scores for all nominees to the Court between 1937 and 2022:

Nom.
Order
Nominee !Chief
Justice
Senate
Vote
Ideology
Score !
Qualifications
Score
Nominator (Party) !Year
1 67 – 18 0.875 0.160 Franklin D. Roosevelt (Democrat) 1937
2 Voice Vote 0.725 0.875 Franklin D. Roosevelt (Democrat) 1938
3 Voice Vote 0.665 0.965 Franklin D. Roosevelt (Democrat) 1939
4 62 – 4 0.730 0.820 Franklin D. Roosevelt (Democrat) 1939
5 Voice Vote 1.000 0.650 Franklin D. Roosevelt (Democrat) 1940
6 CJ Voice Vote 0.300 1.000 Franklin D. Roosevelt (Democrat) 1941
7 Voice Vote 0.330 0.800 Franklin D. Roosevelt (Democrat) 1941
8 Voice Vote 1.000 0.915 Franklin D. Roosevelt (Democrat) 1941
9 Voice Vote 1.000 1.000 Franklin D. Roosevelt (Democrat) 1943
10 Voice Vote 0.280 0.930 Harry S. Truman (Democrat) 1945
11 CJ Voice Vote 0.750 0.785 Harry S. Truman (Democrat) 1946
12 73 – 8 0.500 0.125 Harry S. Truman (Democrat) 1949
13 48 – 16 0.720 0.355 Harry S. Truman (Democrat) 1949
14 CJ Voice Vote 0.750 0.855 Dwight D. Eisenhower (Republican) 1953
15 71 – 11 0.875 0.750 Dwight D. Eisenhower (Republican) 1955
16 Voice Vote 1.000 1.000 Dwight D. Eisenhower (Republican) 1956
17 Voice Vote 0.500 1.000 Dwight D. Eisenhower (Republican) 1957
18 70 – 17 0.750 1.000 Dwight D. Eisenhower (Republican) 1958
19 Voice Vote 0.500 0.500 John F. Kennedy (Democrat) 1962
20 Voice Vote 0.750 0.915 Lyndon B. Johnson (Democrat) 1965
21 Voice Vote 1.000 1.000 Lyndon B. Johnson (Democrat) 1965
22 69 – 11 1.000 0.835 Lyndon B. Johnson (Democrat) 1967
23 CJ 45 – 43 * 0.845 0.635 Lyndon B. Johnson (Democrat) 1968
24 CJ 74 – 3 0.115 0.960 Richard M. Nixon (Republican) 1969
25 45 – 55 0.160 0.335 Richard M. Nixon (Republican) 1969
26 45 – 51 0.040 0.111 Richard M. Nixon (Republican) 1969
27 94 – 0 0.115 0.970 Richard M. Nixon (Republican) 1970
28 89 – 1 0.165 1.000 Richard M. Nixon (Republican) 1972
29 68 – 26 0.045 0.885 Richard M. Nixon (Republican) 1972
30 98 – 0 0.250 0.960 Gerald Ford (Republican) 1975
31 99 – 0 0.415 1.000 Ronald Reagan (Republican) 1981
32 CJ 65 – 33 0.045 0.400 Ronald Reagan (Republican) 1986
33 98 – 0 0.000 1.000 Ronald Reagan (Republican) 1986
34 42 – 58 0.095 0.790 Ronald Reagan (Republican) 1987
35 Withdrawn 0.000 0.320 Ronald Reagan (Republican) 1987
36 97 – 0 0.365 0.890 Ronald Reagan (Republican) 1988
37 90 – 9 0.325 0.765 George H. W. Bush (Republican) 1990
38 52 – 48 0.160 0.415 George H. W. Bush (Republican) 1991
39 96 – 3 0.680 1.000 Bill Clinton (Democrat) 1993
40 87 – 9 0.475 0.545 Bill Clinton (Democrat) 1994
41 CJ 78 – 22 0.120 0.970 George W. Bush (Republican) 2005
42 Withdrawn 0.270 0.360 George W. Bush (Republican) 2005
43 58 – 42 0.100 0.810 George W. Bush (Republican) 2006
44 68 – 31 0.780 0.810 Barack Obama (Democrat) 2009
45 63 – 37 0.730 0.730 Barack Obama (Democrat) 2010
46 Lapsed0.730 1.000 Barack Obama (Democrat) 2016
47 54 – 45 0.110 0.930 Donald Trump (Republican) 2017
48 50 – 48 0.070 0.400 Donald Trump (Republican) 2018
49 Amy Coney Barrett52 – 48 0.230 0.820 Donald Trump (Republican) 2020
50 Ketanji Brown Jackson53– 47 ??Joe Biden (Democrat) 2022
* The vote on Fortas for the Chief Justice position was on cloture and failed to receive the necessary two-thirds majority.

Predictive power

Segal and Cover found that their ideology score is strongly correlated with the subsequent votes of the justices in civil liberties cases, with a correlation of 0.80 and an r² of 0.64.

Segal-Cover scores require subjective assessment of subjective sources. They are not based on any observed voting behavior of judges.[5]

In a 1995 paper revisiting the Segal-Cover score, Segal and his coauthors concluded that the ideology score was significantly more accurate for justices who served during and after the Warren Court . For earlier Court eras Segal et al. (1995) conclude that "scholars should be sensitive to changes in the legal, political, and social environments (which generate the newspaper reactions on which the scores are based) and use appropriate diagnostic tools to tease out their potential effects." They caution that researchers analyzing the ideology of earlier justices should supplement the ideology scores of earlier judges with "other potential determinants of the vote, or redefine their ideological variables to reflect as precisely as possible the issues that their Court addressed."

See also

Notes and References

  1. PhD . Riley . Chad . 2015 . Presented to the Faculty of the Graduate School of The University of Texas at Arlington in Partial Fulfillment of the Requirements for the Degree of DOCTOR OF PHILOSOPHY . The University of Texas at Arlington.
  2. Segal. Jeffrey A. . Cover. Albert D.. Ideological Values and the Votes of U.S. Supreme Court Justices. The American Political Science Review. June 1989. 83. 2. 557–565. 1962405. 10.2307/1962405.
  3. Ideological Values and the Votes of U.S. Supreme Court Justices Revisited. Segal. Jeffrey A. . Epstein. Lee. Cameron. Charles M.. Spaeth. Harold J.. The Journal of Politics. 57. 3. August 1995. 812–823. 10.2307/2960194. 2960194. 145385646.
  4. Web site: The U.S. Supreme Court Justices Database. Epstein. Lee. Walker. Thomas G.. Staudt. Nancy. Hendrickson. Scott. Roberts. Jason. October 2022. April 9, 2023.
  5. Adam . Bonica . Maya . Sen . Estimating Judicial Ideology . Journal of Economic Perspectives . Winter 2021 . 35 . 1 . 10.1257/jep.35.1.97 . 101. free .