Redistricting is a popular topic throughout the country, and especially here in Ohio, where voters just approved a legislatively-referred constitutional amendment on Ohio’s state legislative districts in 2015 and this November will get to vote on a Congressional redistricting ballot measure. An interesting side note to this debate is the US Census’s citizenship question. The 435 seats in the US House are allocated to states based on population after this decennial census.  Critics of the citizenship question have focused on how the citizenship question could have a deterrent effect on census completion and resultantly skew population data to favor Republican-leaning states with lower populations of non-citizens.

But the citizenship question could have further downstream effects in the arena of political representation when you take into account the redistricting process that also occurs after the census.  Under the Equal Protection Clause of the US Constitution and interpreted by various Supreme Court decisions, redistricting must adhere to the principle of one man one vote. A 2016 dispute before the US Supreme Court challenged that this tenet should be based electoral as opposed to representational equality.  The Supreme Court rejected the Plaintiff’s argument a state should be required to draw districts based on the voting-eligible population versus the total number of people in a district.  However, the Court did not say whether states have the permissive authority to apply the law in this manner.
Experts agree that the citizenship question on the census would enable states to decide to draw districts based on voting-eligible versus total population and potentially return this issue to the Supreme Court.  We can assume that a redistricting plan executed according to eligible voters would favor rural regions within states, where there are smaller populations of foreign-born residents than urban areas.
Thus the issue with the census citizenship question is double-edged. If non-citizens are deterred from responding it will impact the allocation of congressional seats.  If non-citizens are not deterred and do respond, it could potentially impact the way the districts are drawn.  Historically, the Supreme Court tried to punt on redistricting issues under the political question doctrine, and when you get down into the weeds on the issue it’s easy to see why.