Racial and Partisan Issues in Voting and RedistrictingDavid Epstein

L6172: Law and Social Science

March 27, 2006

Let’s Start at the Very Beginning… Central result in analytical political science is

Arrow’s Theorem No method of aggregating preferences satisfies

five seemingly innocuous conditions

Contrast with First and Second Welfare Theorems in economics

Implications: Rules aren’t neutral

There’s no one best way to hold elections

Issue: Voting and Representation So voting systems can have a significant

effect on outcomes Any particular group can be over- or under-

represented, depending on the particular scheme

This is what the South did to prevent Blacks from voting post-Reconstruction Grandfather clause White-only primary At-large elections Full-ballot provisions/slates, etc.

1965 Voting Rights Act Primer States would switch to a new tactic if their

current method of disenfranchisement was ruled unconstitutional Literacy tests Poll taxes

This led to the 1965 Voting Rights Act (VRA) Section 2

Swept away all states laws imposing “tests or devices” on any individual’s right to vote

Made illegal all state & local laws that “deny or abridge” minorities’ right to vote

Permanent and (relatively) uncontroversial

1965 Voting Rights Act Primer Section 5

Covered states must receive federal approval for changes in laws that may affect voting Changes in Electoral Systems (but not legislative rules) Annexation/De-annexation of suburbs Redistricting

Not permanent; up for renewal in 2007 Implementation

Standard for preclearance was retrogression I.e., couldn’t go back to at-large elections

Unclear how this applies to redistricting Assumption was that you would pass if you didn’t

reduce the number of majority-minority districts

Early Successes of the VRA Most immediate impact was to allow blacks to

register and vote in the South Black registration was ~5% in Mississippi before the

VRA Now White and Black voters register and vote in the same

proportion Under Section 2, many at-large systems were

replaced with districts Then Court said that discrimination had to be intentional

(Mobile v. Bolden, 1980) Congress responded with a results test in 1982 extension

Thornburg v. Gingles New Section 2 results clause was

implemented in a three-prong test:1. Minority community is cohesive;

2. Majority votes sufficiently as a bloc to usually defeat the minority’s preferred candidate; and

3. The minority is large enough to form a majority in at least one single-member district.

Needed to measure how many voters of one race vote for candidates of the other race.

Ecological Regression Do this by using ecological regression

Calculate votes for black and white candidates as a percent of total turnout

Run two regressions:1. %Votes(Black Cand.) = a + b*(%Black Voters)2. %Votes(White Cand.) = a + b*(%Black Voters)

Then calculate 1. Black Support Black Candidate2. Black Support White Candidate3. Black Rolloff

And the same for white voters

Ecological Fallacy First issue: allow covariates?

No, since we don’t care why voters of one race cast their ballots in a particular way.

Second issue: ecological fallacy Don’t know if the trend is due to changes in voter

behavior, or different types of voters E.g., white who live near blacks may vote differently

from those in surrounding areas No way to separate these two with aggregate level data

Current situation: use better and better statistical techniques to do the best you can with your data (EI)

Representation and the VRA A central debate on the VRA over the past 10-

15 years has centered on the tension between Descriptive Representation: A minority group

can elect its candidates of choice to office; and Substantive Representation: Policies favored by

the minority community are passed into law. Is there a tradeoff between these goals? If so, which should states be forced/allowed

to pursue, e.g., when redistricting?

Georgia v. Ashcroft These issues are becoming even more acute

now, in light of the most important Supreme Court decision on the VRA in recent years. Georgia had reduced black populations in

concentrated minority districts. DOJ refused Section 5 preclearance, arguing that

the districting plan was retrogressive. Supreme Court overruled, said that states could

legitimately pursue substantive representation. Opens the door to more of this type of tradeoff.

The Coming Debate Congress is soon going to have to consider

exactly these issues, as it decides what to do with Ashcroft in a renewed Section 5.

These issues are important not just with respect to the VRA and its renewal. How do we think about the goals and purposes of

political representation in democracies? How can institutions best afford minorities

influence over policy in a majoritarian system?

Pre-Ashcroft Preclearance Based on number of minority(-supported)

candidates elected to office. This, in turn, was measured by the number of

districts effectively controlled by minorities. Used to be “65% rule” Then changed to majority-minority

In the 1990’s, the DOJ forced southern states to create more majority-minority districts. Often bizarrely shaped…

Louisiana 4th (Black majority)

“Mark of Zorro”

New York 12th (Hispanic Maj.)

“Bullwinkle”

Illinois 4th (Hispanic majority)

“Pair of Earmuffs”

Georgia 11th (Black majority)

“French Poodle Attacking with a Hatchet”

Retrogression and Polarization The counting-districts approach to assessing

retrogression works best when districts are either minority-controlled or not. Districting becomes a “black-and-white” issue

This implicitly assumes high degrees of polarization in the electorate.

When polarization decreases, this approach breaks down. (Pildes 2002)

0.5

1P

roba

bilit

y of

Ele

ctin

g B

lack

Rep

.

0 50 57.5 100Percent Black Voting Age Population

Electability: High Polarization

% BVAP

0

P*

50 100

HighPolarization

Measuring Descriptive Representation

% BVAP

0

P*

50 100

No Minority Control

HighPolarization

Measuring Descriptive Representation

Minority Control

0.5

1P

roba

bilit

y of

Ele

ctin

g B

lack

Rep

.

0 40 50 100Percent Black Voting Age Population

Electability: Low Polarization

% BVAP

0

P*

50 100

No Minority Control

HighPolarization

Measuring Descriptive Representation

Minority Control

% BVAP

0

P*

50 100

LowPolarization

% BVAP

0

P*

50 100

No Minority Control

HighPolarization

Measuring Descriptive Representation

Minority Control

% BVAP

0

P*

50 100

Coali-tional

LowPolarization

% BVAP

0

P*

50 100

No Minority Control

HighPolarization

Measuring Descriptive Representation

Minority Control

% BVAP

0

P*

50 100

PS

Coali-tional

ProbableControl

LowPolarization

% BVAP

0

P*

50 100

No Minority Control

HighPolarization

Measuring Descriptive Representation

Minority Control

% BVAP

0

P*

50 100

SafeControl

PS PP

Coali-tional

ProbableControl

Packing

LowPolarization

% BVAP

0

P*

50 100

No Minority Control

HighPolarization

Measuring Descriptive Representation

Minority Control

% BVAP

0

P*

50 100

No Minority Control

SafeControl

PS PP

Coali-tional

ProbableControl

Packing

LowPolarization

PI

Influence

% BVAP

0

P*

50 100

No Minority Control

HighPolarization

Measuring Descriptive Representation

Minority Control

% BVAP

0

P*

50 100

No Minority Control

SafeControl

PS PP

Coali-tional

ProbableControl

Packing

LowPolarization

PI

Influence

How to make tradeoffs?

Need for New Standards Current situation is characterized by low(er)

polarization over the past 30 years. Now 15-20% net crossover in the South.

Need a standard for retrogression in descriptive representation not based on district categories. State may show that “gains in the plan as a whole

offset the loss in a particular district.” Also evidence of an emerging tradeoff between

substantive and descriptive representation. Ashcroft addresses this directly for the first time.

Substantive

DescriptiveParetoFrontier

Ashcroft & Substantive Representation

Substantive

Descriptive

SQ

ParetoFrontier

Ashcroft & Substantive Representation

Substantive

Descriptive

SQ

1

2 3

4

ParetoFrontier

Ashcroft & Substantive Representation

Substantive

Descriptive

SQ

1

2 3

4

ParetoFrontier

Ashcroft & Substantive Representation

Pre-Ashcroft

X X

Substantive

Descriptive

SQ

1

2 3

4

ParetoFrontier

Ashcroft & Substantive Representation

Post-Ashcroft

X

Substantive

Descriptive

SQ

1

2 3

4 P

ParetoFrontier

Ashcroft & Substantive Representation

X

A move to P is now non-retrogressive,if supported by minority community.

Measuring Representation Ashcroft thus calls for

A new measure of descriptive representation based on a statewide assessment of electoral possibilities

A consistent measure of substantive representation that can be used to prospectively evaluate districting plans

Social science has well-developed methods to address both of these issues Calculating the probability of electing different types of

representatives, based on district characteristics Summarizing voting behavior in legislatures

These are continuous measures, avoiding the categorization problem

1. Determine relationship BVAP Roll Call Voting in Congress (Representation Effect)

BVAPVSE ,θ|

RepresentationEquation

Methodology To measure expected substantive representation:

BVAPVSE |

2. Determine relationship BVAP Type of Representative Elected (Electoral Effect)

BVAPP |θ

ElectoralEquation

θ

3. Combine 1 & 2 to calculate average expected Vote Score across districts.

Electoral Equations Collect outcomes for all relevant elections Estimate BVAPType Elected

Republican White Democrat Black Democrat (“Candidate of Choice”)

This yields the probability that each type of representative is elected, given district BVAP

0.5

1

0 .2 .4 .6 .8 1bvap

1975 to 1980

0.5

1

0 .2 .4 .6 .8 1bvap

1981 to 19860

.51

0 .2 .4 .6 .8 1bvap

1987 to 1992

0.5

1

0 .2 .4 .6 .8 1bvap

1993 to 2000

Probability of Electing Different Types of Representatives

65.4% 42.2%

Southern Congressional Districts

Representation Equations

Collect all individual votes in the legislature. For each vote, determine which way the majority of

minority representatives cast their ballots Count this as a vote in the “right” direction

For each legislator, calculate the percent of times they voted with the black majority This is their “Black Support Score” Can weight by degree of unanimity among black reps.

For each subgroup, estimate BVAPSupport Score

.2.4

.6.8

1B

lack

Sup

port

Sco

re

0 .1 .2 .3 .4Black Voting Age Population

1975 to 1980

.2.4

.6.8

1B

lack

Sup

port

Sco

re

0 .2 .4 .6Black Voting Age Population

1981 to 1986.2

.4.6

.81

Bla

ck S

uppo

rt S

core

0 .2 .4 .6Black Voting Age Population

1987 to 1992

.2.4

.6.8

1B

lack

Sup

port

Sco

re

0 .2 .4 .6 .8Black Voting Age Population

1992 to 2000

Substantive Representation, South

The Emerging Pareto Frontier

95

96

97

9899

100 101

102

103

104

105

.5.5

2.5

4.5

6.5

8.6

Pe

rcen

t of V

ote

s A

gre

eing

with

Bla

ck M

ajo

rity

.03 .05 .07 .09Percent Black Democrats Among All Representatives

All Districts

Georgia’s Gerrymander

Range Baseline Proposed

0-25 31 26

25-40 11 17

40-50 2 0

50-60 2 8

60+ 10 5

Plan: Reallocate black voters to elect Democrats

Is This Retrogression?

Georgia Legislative Elections, 1991-2002

0.2

.4.6

.81

Pro

babi

lity

of E

lect

ion

0 .25 .5 .75 1Black Voting Age Population

Republicans White Dems Black Dems

Georgia Black Support Scores, 1999-2002

.4.6

.81

Bla

ck S

uppo

rt S

core

0 .2 .4 .6 .8Black Voting Age Population

Republicans White Dems Black Dems

Descriptive Representation

Plan Influence Coalition Maj-Min E(CoC)

Baseline (1999) 12 1 10 11.2

Baseline (2000) 12 1 12 13.6

Proposed 17 0 13 12.5

Interim (2002) 17 0 13 12.9

Slight fewer candidates of choice elected.

Substantive Representation

Increase in mean and median vote scores.

Plan Mean Median

Baseline (1999) 59.0% 46.1%

Baseline (2000) 62.3% 50.2%

Proposed 66.6% 75.9%

Interim (2002) 65.9% 69.2%