A year and a half ago I wrote two posts on the question of “who counts for representation?” That is, how do you calculate the numbers for apportioning seats between different states, or for equalising the size of districts within a state – do you count total population, or enrolled voters, or something else?
Anyone who’s interested in the question should check out a new scholarly paper on the topic by Nicholas Stephanopoulos and Jowei Chen, called “Democracy’s Denominator” (forthcoming in the California Law Review). They address specifically the effort by Republicans in the United States to have districts drawn so as to equalise not population, as at present, but the number of adult citizens – citizen voting age population, or CVAP.
Stephanopoulos and Chen briefly discuss the principled justifications for the move, concluding (correctly, in my view) that a good case can be made either way. But their main focus is on the claim by Republicans that it would work to their political advantage: they use a set of simulated redistributions (“randomised redistricting”) in ten states to assess how much partisan effect the move would have.
Their conclusion is that it would be rather small. While the shift to CVAP would create more Republican seats, the difference would be “generally not enough to disturb the partisan balance of power” – although as one would expect, it would be greatest in states like Florida and Texas where the non-citizen share of the population is relatively high. They particularly note that the effect of partisan gerrymandering is enormously greater.
It’s a very interesting paper, although as is sadly common in America, it tends to treat the country’s problems in isolation. There is no reference to the fact that countries like Australia have been drawing districts based on something very like CVAP for decades. (Although Stephanopoulos has also recently published a nice comparative study on the work of redistribution commissioners.)
As a result, Stephanopoulos and Chen miss out on what I think is the most compelling reason for using total population in a country like the US without compulsory voting or enrolment: namely that the alternative is not a single uncontroversial statistic like CVAP, but a host of difficult questions. As I put it in 2019:
Should we exclude unlawful immigrants from the relevant numbers? What about lawful permanent residents who are not citizens? And why stop there – what about citizens who are below the legal voting age? Or those who are eligible to vote but not enrolled? Or who are enrolled but don’t bother to turn up? Or do but vote informal?
Compulsory enrolment in Australia, aided by our tradition of impartial electoral administration, gives us numbers that are relatively free from controversy. Without those, the US may well be better off just relying on population. But Republicans, in pursuit of even a small electoral advantage, will probably try the move to CVAP in some states, and with a conservative majority on the Supreme Court it is unlikely that a challenge to it would be successful.
Better still, of course, would be to move away from single-member districts, which would take the sting out of the whole debate. But that seems to be still a long way off.