Abstract
Fair maps are the foundation of a representative democracy. Gerrymanderers wish to create an unrepresentative legislature. The counter to gerrymandering is a fair map where the party sharre of districts matches the party share of the statewide votes. This redistricting criterion was recently codified in the Ohio State Constitution. https://www.legislature.ohio.gov/laws/ohio-constitution/section?const=11.06 A Guide to a new approach for drawing fair maps has been written for citizens, advocates and members of redistricting commissions, as well as legislators and judges. This Guide includes a test for gerrymandering. A research article details, justifies and applies the approach. As more people become aware of approaches such as this, more are likely to ask, “Why aren’t we using procedures like this to build maps where the districts are compact and the maps are fair?”

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