Does gerrymandering make Democratic and Republican congressional representatives more extreme?

Last updated: February 21, 2022
There is no consensus in the literature on this question. We encourage you to read the study summaries below or the studies themselves if you have access.
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2
YES ANSWERS
9
NO ANSWERS
1
NO DATA ON ANSWER


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SUMMARIES OF STUDIES
Total studies in list: 12
Sorted by publication year
1
Partisan Polarization in the United States: Diagnoses and Avenues for Reform
"Over the several decades, observers of American politics have noted the sharp increase in partisanship and ideological polarization among members of Congress. While better ideological differentiation may provide voters clearer choices and increase accountability, the results of recent partisan and ideological battles have raised questions about the impact pf polarization on good governance.While much scholarly effort has gone into studying the root causes on congressional polarization, such research has been hampered by its sole reliance on the US House and Senate for data on legislative polarization. But new data on polarization of state legislatures provided by Shor and McCarty (2011) and updated with the generous support of the John and Laura Arnold Foundation expands our capacity to uncover the political, economic, and social factors that underlie our increasingly polarized system.In this report, we review the evidence concerning the polarization of the US Congress and supplement it with analyses based on the experience of polarization in the US states. We show that while there is variation in polarization across states, in aggregate the patterns are very similar to the national experience. Moreover, analyses of the causes of polarization at the national level are generally confirmed by the data on the states. The richer data from the sates, however, allows us to address new sets of questions which suggest some limited opportunities for reforms targeted at reducing polarization."
AUTHORS
Boris Shor
Nolan McCarty
PUBLISHED
2016 SSRN
No
No
2
Reducing Polarization: Some Facts for Reformers
"In response to the governance problems associated with excessive party polarization in American national and state governments, many reformers now seek to alter existing electoral institutions to reduce polarization and its effects. Unfortunately, many existing proposals are based on premises that lack empirical foundation. This essay outlines a set of empirical regularities about polarization in the United States that have important implications for the appropriateness and efficacy of reform proposals. In the conclusion, I outline some approaches to polarization that do not run afoul of the facts."
AUTHOR
Nolan McCarty
PUBLISHED
2015 University of Chicago Legal Forum
No
No
4
AUTHORS
Michael McDonald
Micah Altman
PUBLISHED
2015 American Gridlock: The Sources, Character, and Impact of Political Polarization
Couldn't Identify
Couldn't Identify
5
AUTHOR
Nathan S. Catanese
PUBLISHED
2014 Notre Dame J.L. Ethics & Pub. Pol'y
Yes
Yes
6
The Gerrymanderers Are Coming! Legislative Redistricting Won't Affect Competition or Polarization Much, No Matter Who Does It
"Redistricting received substantial attention in the popular media in 2011, as states redrew state legislative and congressional district boundaries. Many reformers continue to argue for a de-politicization of the redistricting process, claiming that partisan redistricting is responsible for declining electoral competition and increasing legislative polarization. Our analysis of evidence from state legislatures during the last decade suggests that the effects of partisan redistricting on competition and polarization are small, considerably more nuanced than reformers would suggest, and overwhelmed by other aspects of the political environment."
AUTHORS
Gerald C. Wright
Jonathan Winburn
Seth E. Masket
PUBLISHED
2012 Political Science & Politics
No
No
7
AUTHOR
Nolan McCarty
PUBLISHED
2009 Political Science Quarterly
High Quality Source
No
No
8
Does Gerrymandering Cause Polarization?
"Both pundits and scholars have blamed increasing levels of partisan conflict and polarization in Congress on the effects of partisan gerrymandering. We assess whether there is a strong causal relationship between congressional districting and polarization. We find very little evidence for such a link. First, we show that congressional polarization is primarily a function of the differences in how Democrats and Republicans represent the same districts rather than a function of which districts each party represents or the distribution of constituency preferences. Second, we conduct simulations to gauge the level of polarization under various “neutral” districting procedures. We find that the actual levels of polarization are not much higher than those produced by the simulations. We do find that gerrymandering has increased the Republican seat share in the House; however, this increase is not an important source of polarization."
AUTHORS
Howard Rosenthal
Keith T. Poole
Nolan McCarty
PUBLISHED
2009 American Journal of Political Science
High Quality Source
No
No
9
Redistricting and Party Polarization in the U.S. House of Representatives
"The elevated levels of party polarization observed in the contemporary Congress have been attributed to a variety of factors. One of the more commonly recurring themes among observers of congressional politics is that changes in district boundaries resulting from the redistricting process are a root cause. Using a new data set linking congressional districts from 1962 to 2002, we offer a direct test of this claim. Our results show that although there is an overall trend of increasing polarization, districts that have undergone significant changes as a result of redistricting have become even more polarized. Although the effect is relatively modest, it suggests that redistricting is one among other factors that produce party polarization in the House and may help to explain the elevated levels of polarization in the House relative to the Senate."
AUTHORS
David W. Rohde
Charles J. Finocchiaro
Michael H. Crespin
Jamie L. Carson
PUBLISHED
2007 American Politics Research
High Quality Source
Yes
Yes
12
Evaluating the Impact of Redistricting on District Homogeneity, Political Competition, and Political Extremism in the U.S. House of Representatives, 1962-2002
"We investigate the link between the increased political homogeneity of U.S.House districts over the 1962-2002 period, and the well-known increase in politicalextremism that occurred over that same time period (the “emptying out of the center”).We examine the central mechanism through which this link is posited to act: increaseddistrict homogeneity leading to reduced district competitiveness leading, in turn, to fewercentrist candidates. We argue that this argument, now accepted as gospel in op-ed pagesthroughout the country, has been much overstated. While district homogeneity has risen(using the Koetzle, 1998 measure), and there is a clear link between increased districthomogeneity and declining district competitiveness, the standard Downsian story inwhich political competitiveness can be expected to generate centrist politics is far toosimplistic. In fact, for Republicans there is no relationship whatsoever between districtcompetition and ideological extremism (using D-Nominate scores), and the relationshipfor Democrats has changed sign over the course of four decades and the magnitude of theeffect has never been that large. Also, a reduction in mean district homogeneity is not theonly reason for the observed decline in political competitiveness; realigning trends alsohave a lot to do with the decline in competitiveness. Both Democrats and Republicans arenow more closely tethered to their national party images than was true in the past, thusmaking it harder for a candidate of the party misaligned with the district median to win anelection. Moreover, polarizing trends are also clearly visible in the Senate, where therehas been no change in the political homogeneity of states, although there has been a slightdecrease in number of competitive Senate contests over this period. Thus, blamingredistricting for the bad things (reduced competitiveness, increased polarization andvitriol) recently happening in the U.S. House of Representatives is very much anoverstatement."
AUTHORS
Bernard Grofman
Thomas L. Brunell
PUBLISHED
2005 University of California, Irvine
No
No