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John Roberts’s disproportionate error

June 27th, 2019, 1:05pm by Sam Wang

Today, the Supreme Court ran away from the question of partisan gerrymandering. Chief Justice Roberts’s majority decision cited the problem of “proportional representation” as an impediment to establishing a standard of fairness. His argument has a major logical problem which is easily fixed – though at this point, it will have to be done in state courts. Here’s how.

Roberts asserts that claims of partisan gerrymandering rely on an assumption about what would be appropriate levels of representation. Specifically, he says that the number of seats is not guaranteed for a given number of votes cast statewide – a quota of sorts. (Note that although he says “proportional representation,” he doesn’t mean literal proportionality. He means any diagnostic tool that uses the number of seats won by either party, compared with their vote share.)

To be sure, some tests count wins and losses. The efficiency gap comes to mind, as well as a well-established measure called “partisan bias.” But not all tests do that.

In several law articles [Harvard Law Review Blog]  [Election Law Journal] I argue that the tests fall into two categories:

  1. Inequity of opportunity: did both parties have similar opportunity to win seats?
  2. Inequity of outcome: did the parties get a fair share of seats?

Roberts has focused on category (2). But category (1), inequity of opportunity, fits very well with previous doctrine – which has focused on race as a factor. Was a group packed? Then they would have lopsidedly large wins. Was a group cracked between districts? Then their opponents would have carefully arranged, narrow wins.

Here are some tests that probe for inequity of opportunity:

  • The lopsided-wins test: in a closely-divided state like North Carolina, does one side have more lopsided wins than the other? The t-test does this. As students of science and engineering know, this is literally the oldest test in the book. [Stanford Law Review]
  • In a party-dominated state like Maryland, were the wins engineered to be very uniform, thus protecting the majority party? Again, it’s a simple test – and again, it doesn’t count the number of wins. [Election Law Journal]

Finally, if the Court didn’t want to get into math, they could have done what they’ve always done in racial gerrymandering cases: inspect individual districts for evidence of packing and cracking.

So basically their reason for not addressing partisan gerrymandering is at best a misunderstanding of the detection methods; at worst, it’s a clever dodge.

Would pointing all this out to the Supreme Court have swayed them? I doubt it. Fundamentally, I suspect Roberts didn’t want to address these cases at all. If in her dissent Justice Kagan had cited the arguments I’ve written about, I am sure Roberts would have found another excuse.

Although federal courts are now closed, state courts are wide open – indeed, Roberts leaned on this point fairly hard. And all the data-based arguments for partisan gerrymandering can still work in state court. We’ve built a legal doctrine that finds relevant principles in all fifty state constitutions. [U. Pennsylvania Journal of Constitutional Law, forthcoming] In North Carolina, where plaintiffs lost in today’s Supreme Court decision, the state supreme court is friendly to voting rights. There’s a lot of hope for the Tar Heel State.

The dream of fair districting lives on!

Tags: Redistricting · Supreme Court

10 Comments so far ↓

  • Phil Felton

    So Sam, State courts can rule on gerrymandering but federal courts can’t, have I got that right?

  • Rachel Findley

    Right. We just dust ourselves off and carry on. Never give up. So glad to see the effort going forward in the states.

  • Russ Abbott

    Thanks for not giving up!

  • marshall flax

    One of the social roles of elections and the associated system of “rule of law” mores is to give to governments a cloak of legitimacy.

    Today I think that the circuit courts should exclude Kavanaugh’s illegitimate vote and treat the decision as they would treat any 4-4 tie.

  • bks

    Hopefully Sam will now return to analysis of the 2020 election cycle. With regards to 2016, let me quote the greatest speed chess player of his generation, Steve Brandwein: “The odds on a heavyweight championship fight should never exceed 10:1.”

  • Allen Kamp

    Petition of the Chickens to the Chicken Protection Agency

    We, the chickens of Henhouse 101 hereby petition The Chicken Protection Agency for protection against the foxes as they are eating us alive.

    Sincerely, Chickens

    Decision of the Chicken Protection Agency in response to the Petition of the chickens

    Dear Hens and Roosters,

    We have we have carefully considered your petition and sympathize with your position, even to the extent of feeling your pain.

    Unfortunately, we are unable to offer any protection because this is what is known as “a fox question” which is beyond our competence to consider or act upon. To answer it, we would have to determine the level of involvement of the foxes which is impossible to do. The question is therefore “nonagencable” by this Agency.

    While we are saddened by our inability to act, we are confident that you can find protection from many sources, especially the foxes`.

    Decided June 28, 2019, The Chicken Protection Agency.

    • Pechmerle

      Per A. Lincoln and A. Stevenson:
      “It hurts too much to laugh, and I’m too old to cry.”

  • NotJamesMadison

    At the end of his opinion Chief Justice Roberts cites a 2010 bill, H. R. 6250, (available at that “would have required States to follow standards of compactness, contiguity, and respect for political subdivisions in redistricting. It also would have prohibited the establishment of congressional districts “with the major purpose of diluting the voting strength of any person, or group, including any political party,” except when necessary to comply with the Voting Rights Act of 1965.”

    I have just had a look at this bill and it appears to me that it would be a good start for a federal statute requiring fairly drawn congressional districts. (I suspect it over-constrains the problem but would be the first to agree that I’m probably become too mathematically decrepit to do more than be suspicious.)

    Could someone have a look at this bill and see what the most extremely pro-Republican map would have been in North Carolina following the 2010 census.

    Would you believe that this bill was submitted by Devin Nunes of all people! On Sept. 29, 2010, the day Congress adjourned for the 2010 election (until Nov. 15).

  • Stu Weisbrod

    So how does one deal with Democrat states playing for “fair re-districting” while GOP states continue their efforts to gerrymander??

    How is that fair and does that not build the kind of “minority rule” that the GOP seems to relish these days by taking 50/50 states and turning them into highly partisan breakouts such as NC, PA (now fixed), and others, that favor only their party?

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