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Published Papers

"Estimating the Ideal Points of Organized Interests in Legal Policy Space"

Scholars have been limited in the development and testing of theory regarding the incidence and impact of organized interest advocacy at the U.S. Supreme Court due to a critical measurement issue - the inability to properly locate these interests in the legal policy space in which the Court operates. We treat the positions articulated by organized interests in their amicus curiae briefs as “votes” in Court cases, allowing us to use an IRT model to estimate the locations of both the 600 most active organized interests and the justices in the same legal policy space. The resulting ideal point estimates yield substantive implications (e.g., the distribution of organized interest ideal points is slightly to the left of the justices) and lend themselves to a number of future applications to important questions involving judicial politics in the United States.

"Locating U.S. Solicitors General in the Supreme Court’s Policy Space"

The U.S. Solicitor General (SG) is widely viewed as a particularly consequential legal and political actor and is the most direct link between the executive branch and the Court. Spatial approaches to understanding the involvement and influence of the SG at the Supreme Court make it necessary to locate the SG in the same policy space as the justices. We treat the SG’s positions advocated in her amicus curiae briefs as equivalent to votes in these cases and employ an item response model that yields facially valid estimates of the location of the SGs serving during the Eisenhower through Obama administrations. Ideal points for the justices are simultaneously estimated, meaning that we provide directly comparable ideal points for the justices and “tenth justices” in the same policy space. An examination of the location of the SGs reveals that the ideological orientation of the appointing president has a strong effect. We find mixed evidence of SGs orienting themselves toward the median justice on the Court, implying that SGs might also serve a second principal in some cases.


Working Papers

"State Advocacy and Representation at the U.S. Supreme Court"

The states are amongst the most active, important, and effective actors involved at the U.S. Supreme Court.  To estimate the locations of the states in the Supreme Court’s policy space, we rely on their amicus curiae filings at the Court and treat the positions taken in these briefs as akin to the votes cast by the justices in these cases.  Armed with data on these “votes” by the states and the justices, we estimate their ideal points and find that 1) the states occupy a more conservative region of legal policy space than the justices do, and 2) there has been an increasing polarization of the positions expressed by the states as a function of the partisanship of the attorneys general representing them.  We then turn to developing a simple model of the location of the states over time and show that, while there is evidence that a state’s position is responsive to the preferences of its citizens, the partisanship of the attorney general has a much bigger effect. This calls into question the strength of the representational linkage between the public and the advocacy activities of their states.


This material is based upon work supported by the National Science Foundation under Grant No. SES-1351922. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation.