Testimony in a fast-tracked lawsuit alleging gerrymandering got underway in Pa. Commonwealth Court Monday. The case could force a new state congressional map before the 2018 midterm election. Eighteen registered Democrats — one from each congressional district — claim Pennsylvania’s map was drawn unfairly by state GOP leaders to advantage Republicans. Congressional maps have to follow certain rules, such as distributing equal numbers of voters between districts. Advocates for fairer congressional maps say it’s also a best practice to avoid dividing counties and municipalities when drawing district boundary lines.
The plaintiffs’ first witness, political scientist Jowei Chen, testified that this clearly wasn’t adhered to in Pennsylvania.
Chen, who’s published a handful of peer-reviewed studies of redistricting and political geography, used computer models to generate 1,000 random simulations of Pennsylvania’s congressional map. On average, these versions divided less than half as many counties as the current one.