Ask the Expert: What is redistricting, and how does it affect political power?

October 7, 2020 - Caroline Brooks

Fair or not, whether Democrats or Republicans hold the majority power in Congress isn’t in the hands of voters. Where certain district lines are drawn within states – which are determined based on changes in population – dictates who holds a seat in the U.S. House of Representatives and in many state senates.

“Redistricting,” as it’s called, is a hot-button issue across the country and every 10 years, it can change how a state votes.

Jon Eguia, a professor in Michigan State University’s department of economics, researches partisan advantages in redistricting maps. Sponsored by the Institute of Public Policy and Social Research, the goal of Eguia’s research is to help draw maps that provide no “disproportionate advantage to any political party.” He has presented findings his research at Harvard University and at the NYU School of Law, and recently was a co-panelist with Michigan’s Secretary of State regarding the upcoming redistricting drawing in 2021.

Eguia explains the complicated process of redistricting, and how the public can participate.

1)     What exactly is redistricting and how does it work?

"Redistricting is the process of drawing electoral district maps. Once these districts are drawn, in each election, voters in each district elect one representative from the district to take a seat in a legislative chamber, such as the U.S. House of Representatives, or, closer to home, the Michigan House or Senate.

"In the United States, redistricting happens every 10 years, after the Census. Since each district must have the same population, when population changes, maps must change too."   

2)     As we’ve seen in past elections, the Electoral College can throw off results of a whole election. How does redistricting relate to the Electoral College?

"There are two ways to assign seats to different geographic areas: apportioning and redistricting. Apportioning keeps a map of districts fixed and assigns a number of seats to each district according to its population. This is how the Electoral College assigns seats to the 50 states: state borders never change, so each state gets two seats, plus additional seats assigned based on its population.

"Redistricting keeps the assignation of seats to districts fixed at one seat per district and deals with changes in population by changing the district boundaries. This is how the U.S. House of Representatives, and most state legislatures, including Michigan, work. The Electoral College does not need to redistrict because it uses the apportionment method to redistribute seats across states with changes in population."

3)     Is every state in the U.S. “redistricted” similarly? Are some more fair than others?

"Every state must follow some minimal rules set in federal law. Beyond that, each state is free to set up its own rules and its own processes for redistricting. Surely, some are fairer than others. Here in Michigan, for instance, we just amended our own state constitution to explicitly require “partisan fairness,” that is, that the maps be fair to all parties. While the maps we used in Michigan from 2012 to 2018 and are using now in 2020 are among the least fair in the nation, I’m optimistic that with the new state rules, the maps for 2022 to 2030 will be much fairer."

4)     How long have districts been drawn the way they are in Michigan? In the U.S.?

"The way districts are drawn has evolved over time. At the roots of American democracy, most of the assemblies in the 13 colonies and in the original founding states used the apportionment method to assign seats to counties and townships, so they did not need to draw districts.

"Since the 1840s, Congress has mandated that states draw district maps and elect one representative per district for the U.S. House of Representatives. Redistricting became much fairer once a pair of Supreme Court rulings in the 1960s required districts to have equal population.

"The redistricting that followed the 2010 census suddenly became less fair as partisan mapmakers used newly available information, technology and software to draw maps that greatly favor one party while respecting the equal population requirement. State court rulings, civic activism and constitutional reforms over the past few years have served as a corrective of these excesses in many states, including in Michigan, where the constitutional amendment of 2018 I mentioned above removed the power to draw district maps from the state assembly, and put it in the hands of an Independent Citizen Commission."

5)     What is the Independent Citizen Commission is, what is it doing, and how your research is informing it.

"The Independent Citizen Redistricting Commission is a group of 13 regular citizens – four of them supporters of the largest party, another four supporters of the second largest party, and five independents or supporters of smaller parties. The members – who were selected from nearly 10,000 applicants in the summer of 2019 – are tasked with drawing electoral district maps that Michigan will use from 2022 to 2030.

"I served in an orientation panel during the first day the Redistricting Commission met in September. My research studies how to measure whether a redistricting map is “fair,” and how to quantify how much it favors one party over another. Those of us working at public universities in the State of Michigan are a resource that the Commission can use if it wishes to draw upon our knowledge or expertise as it prepares to draw fair maps for all Michiganders.

"All the Commission meetings are open to the public, and you can follow them live on YouTube or Facebook. They are also hiring! You can follow their progress at"

6)     Is there anything the public can do to change unfair redistricting?

"Yes! In Michigan, the public already did the hard work, amending the Michigan Constitution through a successful ballot initiative! Now all Michiganders can help by engaging with the Commission, participating in its meetings, telling the commissioners about your community and how you would like it to fit within the district maps for the State. Michiganders can also help by encouraging the few partisan politicians and lobbyists who are still fighting against the Independent Citizen Commission, to drop their attempt to subvert its work, and to instead embrace the new, fairer, and more transparent system of redistricting that a large majority of Michigan voters made possible by reforming the state constitution in 2018."