Nicholas Stephanopoulos University of Chicago Law School

1. Nicholas Stephanopoulos
University of Chicago Law School
The Garden State Model?
Redistricting Commissions and the
New Jersey Experience
Paul Simon Public Policy Institute
Redistricting Conference
April 30, 2013

2. Types of Redistricting Commissions
1. Partisan: Unbalanced partisan composition. Often
made up of state officials appointed ex officio. E.g.,
Arkansas, Ohio, Texas.
2. Bipartisan: Balanced partisan composition.
Members often appointed by party leaders. E.g.,
Colorado, New Jersey, Washington.
3. Nonpartisan: Relatively insulated from political
pressures. Citizen body is one option, technocratic
body is another. E.g., California, Iowa, foreign
commissions.

3. New Jersey Background
• Apportionment Commission: Responsible for state legislative
redistricting. Created in 1966. 10 members appointed by
chairpersons of state parties. If they cannot agree on plans, N.J.
Supreme Court Chief Justice appoints 11th member.
• Redistricting Commission: Responsible for congressional
redistricting. Created in 1995. 12 members appointed by state
legislative and party leaders. If they cannot agree on
chairperson, N.J. Supreme Court picks between two contenders
with most votes based on ability and experience.
• Chairpersons: Extremely distinguished individuals including
Prof. Larry Bartels (Princeton), Prof. John Farmer (Rutgers), Prof.
Alan Rosenthal (Rutgers), and Prof. Donald Stokes (Princeton).
Have played very active role in process and prioritized partisan
fairness.

4. Electoral Metrics
Metric Definition
Partisan bias Divergence in parties’ shares of statewide
seats for same share of statewide votes
Efficiency differential Gap between parties’ respective “wasted”
votes
Average margin of victory Average difference in vote shares between
winning and losing candidates
Share of competitive districts Proportion of races decided by less than
twenty points
Electoral responsiveness Rate at which party gains or loses seats given
changes in its statewide vote share
PartisanfairnessCompetitiveness

5. Record of U.S. Commissions – Partisan
Fairness
0%
1%
2%
3%
4%
5%
6%
7%
8%
9%
10%
U.S. House State Legislatures
Legislature Commission
0%
2%
4%
6%
8%
10%
12%
U.S. House State Legislatures
Legislature Commission
Partisan Bias Efficiency Differential

6. Record of U.S. Commissions –
Competitiveness
0%
10%
20%
30%
40%
50%
60%
U.S. House State Legislatures
Legislature Commission
0%
5%
10%
15%
20%
25%
30%
35%
40%
45%
U.S. House State Legislatures
Legislature Commission
0
0.5
1
1.5
2
2.5
U.S. House State Legislatures
Legislature Commission
Average Margin of Victory Share of Competitive Districts Electoral Responsiveness

7. Record of U.S. Commissions - Regressions
Metric Commission Court
U.S. House – partisan
bias 
U.S. House – efficiency
differential
State legislatures – partisan
bias 
State legislatures – efficiency
differential  
U.S. House – average margin of
victory 
U.S. House – share of competitive
districts 
U.S. House – electoral
responsiveness 
State legislatures – average margin
of victory 
State legislatures – share of
competitive districts 
State legislatures – electoral
responsiveness 

8. Record of Foreign Commissions

9. Record of New Jersey Commissions –
Partisan Fairness
0%
2%
4%
6%
8%
10%
12%
U.S. House State Legislatures
Other Commission New Jersey
0%
2%
4%
6%
8%
10%
12%
U.S. House State Legislatures
Other Commission New Jersey
Partisan Bias Efficiency Differential

10. Record of New Jersey Commissions –
Competitiveness
0%
10%
20%
30%
40%
50%
60%
U.S. House State Legislatures
Other Commission New Jersey
0%
5%
10%
15%
20%
25%
30%
35%
40%
45%
50%
U.S. House State Legislatures
Other Commission New Jersey
0
0.5
1
1.5
2
2.5
3
U.S. House State Legislatures
Other Commission New Jersey
Average Margin of Victory Share of Competitive Districts Electoral Responsiveness

11. Concluding Points
1. Properly structured commission can produce real
improvement in partisan fairness
2. If commission ignores competitiveness it will not
arise by accident
3. Bipartisan commission is not optimal model, but if it
is to be used, it should be with highly skilled and
active chairperson