| District | Total Pop. | Pop. Dev. | Dem Votes | Rep Votes | Partisan Margin | Polsby-Popper | Wasted Votes |
|---|
Judicial Doctrines Behind Injunctions
When federal courts or the Supreme Court enjoin a state redistricting map—as occurred with challenged maps prior to general elections—judges scrutinize two primary constitutional dimensions:
1. Article I, § 2 (One Person, One Vote): Congressional districts must be drawn to achieve exact population equality as nearly as practicable (Wesberry v. Sanders, Karcher v. Daggett). Non-zero deviations require rigorous justification.
2. Partisan & Racial Vote Dilution: Intentional cracking (splitting opposition voters across multiple districts to dilute their influence) or packing (cramming voters into one super-majority seat) creates severe partisan efficiency gaps, violating state constitutional guarantees or § 2 of the Voting Rights Act.
Quantifying Gerrymandering Metrics
How is the Partisan Efficiency Gap (EG) Calculated?
The Efficiency Gap measures wasted votes. In each district, all votes cast for a losing candidate are wasted, and all votes cast for the winner beyond the 50% + 1 threshold are wasted. EG is defined as:
EG = (Net Wasted Party B - Net Wasted Party A) / Total Votes Cast
An efficiency gap exceeding ±7.0% or 8.0% creates an entrenched, durable advantage that resists political swing cycles.
What is Polsby-Popper Compactness?
Polsby-Popper computes the ratio of a district's area to the area of a circle with the identical perimeter: PP = 4π × Area / Perimeter². Scores close to 1.0 indicate compact circular or hexagonal shapes; lower scores (<0.20) indicate irregular tentacles drawn to include or exclude specific voter blocks.