Every decade the decennial US census is followed by a tumultuous process of redrawing state voting maps. This process gives states an opportunity to update their voting districts to account for shifting population distributions. In many states, this occurs at three levels: the US congressional districts determined via apportionment to the US House of Representatives, State Senate districts, and State House districts. However, those entrusted with redrawing the maps also wield the power to archi- tect election outcomes for the decade to come. Partisan actors can extrapolate available geographic voting data, polling results, and demographic information to effectively simulate future election outcomes on a variety of districting proposals. Such a manipulation of the geographic boundaries of voting districts is colloquially known as gerrymandering.
While gerrymandering has occurred during the redistricting process since the very beginning of the country’s history, its impact is nowadays far more pronounced. The rapid development of technology and large-scale data processing capacities facilitates effective modeling at the level of census-blocks. Moreover, redistricting has become part of the strategem of both the Democratic and Republican political parties. When political parties control this process and exploit it to choose the voters that elect them, they can provide disproportionate advantage to their party, ensure re-election of incumbents, eliminate competitive elections, disenfranchise particular demographic voting blocs, and generally undermine democratic processes. In this paper, we focus on the implications of ger- rymandering to partisan fairness.