These datasets contain the Martin-Quinn scores for the October 1937 through the October 2013 term of the U.S. Supreme Court. The Justices dataset contains the ideal point estimates and other quantities of interest for each justice in each term. The Court dataset contains court-specific quantities, including the estimated location of the median justice. All datasets are provided as ASCII text files, Stata DTA files, Microsoft Excel spreadsheets, and SPSS SAV files. We ask that if you use these scores in your work, please cite the following article:

Andrew D. Martin and Kevin M. Quinn. 2002. "Dynamic Ideal Point Estimation via Markov Chain Monte Carlo for the U.S. Supreme Court, 1953-1999." Political Analysis. 10:134-153. [PDF]

These scores are based on the July 23, 2014 (2014 Release 01) release of the Supreme Court Database.

THE 2013 JUSTICE DATA FILES
justices.csv
justices.dta
justices.xls
justices.sav

Each file contains these variables:
Variable Description
termTerm
justiceSupreme Court Database unique justice identifier
justiceNameJustice last name
codeSupreme Court Database justice code
post_mnEstimated Martin-Quinn score (posterior mean)
post_sdMartin-Quinn score posterior standard deviation
post_medMartin-Quinn score posterior median
post_025Martin-Quinn score 2.5 percentile
post_975Martin-Quinn score 97.5 percentile

NOTE: We recommend using the posterior mean (post_mn) as the estimate the ideal point of each justice in each term.


THE 2013 COURT DATA FILES
court.csv
court.dta
court.xls
court.sav

Each file contains these variables:

Variable Description
termTerm
medLocation of the median justice (posterior mean)
med_sdPosterior standard deviation of the median justice
minLocation of the minimum justice (posterior mean)
maxLocation of the maximum justice (posterior mean)
justiceJustice most likely to be median
just_prProbability of most likely justice
Harlan-StoneProbabilities each justice is median in each term

NOTE: We recommend using the posterior mean location (med) for the median justice. In order to better understand the Court (including the median justice) in terms with turnover, our Court dataset now includes separate records for terms in which a justice resigned and his or her replacement was confirmed and seated during a term. This happened in the 1937 term (Reed replaced Sutherland), 1938 term (Douglas replaced Brandeis), 1956 term (Whittaker replaced Reed), and the 2005 term (Alito replaced O'Connor).

Please contact us if you have any problems or questions about these measures.

LEGACY DATA FILES
2013 MQ Scores Data
2012 MQ Scores Data
2011 MQ Scores Data
2010 MQ Scores Data
2009 MQ Scores Data
2008 MQ Scores Data
2007 MQ Scores Data
2006 MQ Scores Data
2005 MQ Scores Data
2004 MQ Scores Data
2003 MQ Scores Data
2002 MQ Scores Data
2000 MQ Scores Data
1999 MQ Scores Data
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