Solving Congressional Partisan Polarization One Caucus at a Time

Jennifer N. VictorGeorge Mason

Universityjvictor3@gmu.edu

Nils RingeUniversity of

Wisconsinringe@wisc.edu

Project MotivationsO Follow-up from forthcoming book

O Bridging the Information Gap: Legislative Member Organizations as Social Networks in the United States and European Union, U. Michigan Press, 2013.

O Is the proliferation of caucuses in Congress a response to increased partisan polarization?

O If so, do caucuses alleviate the effects of partisan polarization?

Congress is Polarized

Caucuses are Growing

89119

163 178

227269

303

379419

18

9 9 10

14 13 12

22

26

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103 104 105 106 107 108 109 110 111

Aver

age

Cauc

us Si

ze

Num

ber o

f Cau

cuse

s

Congress

Congressional Caucus Trends103rd-111th (1994-2010)

# of caucuses

avg membership

Caucus Growth and Polarization Correlation

Caucuses are Bipartisan

A modest

Research QuestionO Are opposite-party legislators who

share caucus memberships more likely to vote together than those who don’t share caucus memberships?

O Today: 103rd-111th Congresses (2004-2010)

Co-votingO The frequency with which any pair of

legislators casts the same vote.O DescriptiveO Similar to NOMINATE, but dyadicO Raw roll-call inputsO 864,879 dyads O Mean = 0.68, (Stand. Dev. = 0.21)

Co-votingby co-partisans

02

46

8

0 .5 1 0 .5 1

Opposite Party Same Party

Den

sity

Rate of Co-VotingGraphs by MCs from Same Party

ArgumentO MCs have strong incentives to maintain

communication and relationships with cross-partisans (Huckfeldt and Sprague 1987; Mutz 2006; Ringe, Victor, and Gross 2013)

O Caucuses are voluntary, non-voting groups.O When Congress is more polarized, MCs have

stronger incentives to join bipartisan groups.O As partisanship increases, the bi-partisan

caucus system will grow.O The increased participation in bi-partisan

caucuses reduces overall partisan polarization.

Argument

Increased Partisan

Polarization (in roll calls)

Seek Bipartisan Relationships via

Caucuses

Bi-partisan Caucuses GrowPartisan

Polarization Declines(in ??)

Today’s InferenceO If the argument is true, the we

should observe increased co-voting among caucus-connected opposite-partisans.

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0.2

0.4

0.6

0.8

1

103 104 105 106 107 108 109 110 111

Covo

ting

Rate

Congress

Covoting Rate for House Members 1994-2010, by Co-partisans

Same Party CovoteRate

Opposite Party CovoteRate

Control for other known covariates

O Joint Committee MembershipO From the same stateO Ideological distanceO Same genderO In leadership (party leader,

committee chair)

Dyadic Regression for Opposite-Party Pairs

Coeff. SE T Pr(t)Caucuses 0.0012 0.00005 22.0 0.0Committees 0.0016 0.0002 6.57 0.0State - - - -NOMINATE Dist. -0.236 0.0019 -121.95 0.0

Female 0.0022 0.0043 0.52 0.605Leaders 0.0009 0.0007 1.24 0.213

N= 430,943; R-Squared= 0.75; Pr(F) = 0.00; fixed effects for time included, errors clustered on dyad

InterpretationsO There is an association between opposite-

party voting and caucus participation.O BUT…

O Autocorrelation in the errors (how to build a better statistical model)?

O How to test that caucuses are a result of increased partisanship?

O If MCs join caucuses to overcome partisanship, should we observe it in the roll calls? Causal feedback.

Can Both be True?O Can it be that partisan polarization

remains in the face of increased cross-party voting by caucus members?

O If so, how many MCs would have to participate in the caucus “inoculation” before we would see an effect in roll calls?

Moving ForwardO Treat caucus membership as an

experimental “treatment” effect. Measure the voting behavior of co-members before and after joining the group.

O Include cosponsorship as a covariate.

O Better control for regional covariation.

O Aggregate ties between MCs?