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A Three-Prong Standard for Partisan Gerrymandering

October 8th, 2015, 11:25pm by Sam Wang



In Davis v. Bandemer and Vieth v. Jubelirer, the Supreme Court has held that partisan gerrymandering is justiciable (i.e. within their scope to regulate), but that a manageable standard does not, in their view, yet exist. Here is a draft of my paper on how to define such a standard. Prong #1 is the subject of my Gerrymandering Theorem post below (and my specific mathematical question is described here). Prongs #2 and #3 have well-defined statistical properties, and are in that sense complete.

Tags: House · Politics · Redistricting

14 Comments so far ↓

  • Figs

    Dr. Wang,

    I just read your paper, and I think it’s a very interesting way to move forward. One thought that occurred to me, which is certainly not within the scope of your paper, but arises as a natural (to me) follow-on question: do you foresee a way to combat multi-state gaming of such a standard as the one you proposed?

    That is, the three-prong standard allows ambiguity of results, within certain outlined limits. The increased ability to fine-tune redistricting results could potentially allow legislators to draw maps that give them systemic advantages, in multiple states, that just barely fail to satisfy the three prong test for partisan gerrymandering. We know that there is a national project (REDMAP) to redraw districts in as many states as possible in ways favorable to Republicans. Is there a way that the cumulative effect across several states might be recognized as partisan gerrymandering, even if individual states’ results are not? Would such a question even be justiciable?

  • 538 Refugee

    I just read Ohio’s constitutional amendment to end gerry mandering by taking redistricting out of the hands of elected officials and putting it in the hands of elected officials.

    http://ballotpedia.org/Ohio_Bipartisan_Redistricting_Commission_Amendment,_Issue_1_%282015%29

  • Jay Sheckley

    We just want to thank you for working on this hugely important thing.

    • TaxCutsForTheRich

      This article nearly made me throw up. To think we might have lost an entire decade of partisan gridlock solely due to Karl Rove. That man should be in prison.

      And I’m sick of the “both side do it” crap, which I am glad at least this article solely focused on the unprecedented Republican gerrymandering.

  • Leading Edge Boomer

    Professor Wang, could you include Iowa in your paper? They have had non-partisan redistricting through several censuses, and even Rep. King from the reddest IA district supports this process–maybe because the process would not threaten his fief.

  • Quentin

    I think avoiding maps is a good idea, but I still think it would be interesting to see how well districts that meet your proposed standard do when applying geographic measures of compactness. If districts that meet the proposed standard have a high probability of “looking” non-gerrymandered, that would be a desirable outcome.

    • Sam Wang

      Lots of scholarship using maps. If you like, look up Chen and Rodden for some good recent work.

      Probably won’t go in that direction because maps are already fairly suspect, at least when it comes to the search for a general SCOTUS-acceptable standard. Look at Michigan – pretty straight boundaries there, but seats-votes outcome is screwy. Conversely, meandering boundaries on a single district are actually Constitutional – SCOTUS calls that kind of thing a “political” question.

    • Matt McIrvin

      I’d guess that you could establish districts that violate any geographic standard of compactness, but do fine at avoiding gerrymandering effects. For an extreme case, imagine that every district is split into hundreds of thousands of tiny disconnected parcels, smaller than any neighborhood, scattered at random all over the state. The composition of any such district would be close to that of the state as a whole, so it would be much like having at-large candidates. Minority groups with distinct political preferences would likely be shut out of representation entirely, but it wouldn’t produce any partisan advantage.

    • Matt McIrvin

      …Though I suppose the case I imagined violates Sam’s goal of euproportionality. It’s just winner-take-all.

  • Olav Grinde

    Great! I really do hope your work will have an impact on the law and on legal interpretation.

    Extreme gerrymandering really is one of the strongest factors in the ongoing demise of American democracy.

  • 538 Refugee

    Has this changed significantly since I last saw it? You use the word “draft”? It seems to be getting some views and downloads.

    • Sam Wang

      Yes, the response is pretty good so far. The word “draft” is there to cover me in case I learn of legal errors (this is inevitable). I plan to leave it alone until it gets accepted at a law review. It’s on SSRN so that expert readers can get at it. I’m currently working on a more writeup for a general, nonacademic audience. The “draft” will stay the same until that is done.