why are some districts redrawn after a census?

Question

homework

Answer 1

Redistricting
Redistricting is the process of redrawing state legislative and congressional district boundaries every 10 years by state legislatures following the U.S. Census. Redistricting litigation rages on that will determine the rules for the next round of line drawing. NCSL publishes the definitive work on redistricting law every ten years and collects data about how states do redistricting as well as the outcome of the process including the number of residents in each district.