Redistricting | MIT Election Lab
MIT Election Lab's explainer defines redistricting as the redrawing of legislative district boundaries after each decennial Census to keep districts roughly equal in population, a process that also shapes which party wins seats. It explains gerrymandering tactics like packing and cracking, how legislatures and commissions share mapmaking power across states, and the landmark litigation over partisan and racial gerrymandering, from Reynolds v. Sims (1964) through the Supreme Court's 2026 ruling in Louisiana v. Callais, including the 2025 mid-decade redistricting wave begun in Texas. It also surveys scholarship on gerrymandering's effects and the challenges of auditing local redistricting.
