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:

Qualifications: 0 means unqualified and 1 means extremely qualified Qualification scores are based on the characterization of each editorial as positive, neutral, or negative toward the nominee. Positive articles are coded as 1, neutral articles as 0.5, and negative articles as 0. Ideology: 0 means most conservative, and 1 means most liberal. Ideology scores are based on each editorial's characterization of the nominee as liberal, moderate, conservative, or not applicable. Articles characterizing the nominee as liberal are coded as 1, moderate as .5, conservative as 0; articles deemed not applicable are omitted from the ideology score. 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". 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. 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 ChiefJustice SenateVote IdeologyScore QualificationsScore 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 Lapsed 0.730 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 Barrett 52 – 48 0.230 0.820 Donald Trump (Republican) 2020 50 Ketanji Brown Jackson 53– 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.

A highlighted row indicates that the Justice is currently serving on the Court.

A Senate vote in red text indicates that the nomination was blocked. A question mark indicates that no Segal-Cover score is available for this Justice. 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.

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 Models of judicial decision making Ideological leanings of United States Supreme Court justices Judicial Common Space Supreme Court of the United States

References