The argument, which I attended this morning, was unusually subdued.  I think that’s because the prior case, challenging the Arizona Independent Redistricting Commission’s plan, was tedious and frustrating to the Court, with the lawyers challenging the Commission’s plan not able to give the Court clear, consistent answers regarding their basic theory of the case.  The Court was energetic in the first case but then seemed a bit worn down from the unsatisyfing first argument.  But in terms of how Evenwel is likely to come out, here are my views on six central points:

1.  The Court is not going to hold that voter equality (equal numbers of eligible voters per district) is constitutionally required.  Justice Kennedy showed no interest in that position and asked no questions that suggested he was wrestling with embracing that view.  That is consistent with my view going into the case that it was always unlikely this Court would conclude that voter equality is required.  Some early journalistic coverage of the argument, such as here, portray the Court as likely to adopt the voter equality standard, but I think those stories misunderstand the nature of the questions Justice Kennedy was asking.
2. The Court is not going to embrace the other clean, polar position either, which is that the Constitution requires that total population be the measure.  That issue was not properly teed up for the Court, with none of the counsel before the Court arguing that the Court should adopt total population.  The issue here is whether the Court will expressly leave this question open and keep alive the possibility that, if and when the Court has to confront that question, the Court would then clearly be free to decide that total population is the required standard.
3. So the Court will either affirm the status quo or adopt an intermediate position to which Justice Kennedy appears drawn.  That is the view that states have to at least consider voter equality as one factor to take into account.  He consistently returned to this question and it seemed his central instinct about the case.  Texas acknowledges that it did not take voter equality into account at all (the State Constitution prohibits that) and this case was tossed out at the very first stage of the litigation, on a motion to dismiss.  Justice Kennedy asked more than once whether, given this context, states should have at least the minimal obligation to see whether they could do a better job at diminishing inequalities among eligible voters across districts, without perhaps sacrificing too much other constitutional and redistricting values. If the Court adopts this approach, that would be slicing the issues pretty thinly between the two sides.  If this view prevails, it would impose a process-oriented obligation:  voter equality is a factor that must be “considered.”
4. This would look like a victory for the appellants, but it would be a win on the most minimal grounds.   Moreover, even that holding might be accompanied by qualifications concerning the reliability of the ACS data that counts citizens and non-citizens.  There is a debate among the briefs, reflected at the argument, over the reliability of this data, and I don’t know if the Court would want to resolve that issue for itself in the first instance.  So even this narrow holding might come in this form:  states have to at least consider voter equality, to the extent there is accurate and reliable data on that, and we leave it to the lower courts in specific cases to address that reliability question.
5. If the Court holds that states have to take voter equality “into account” as “a factor,” what would that mean on the ground?  The key question would then become:  how much weight do states have to give this factor, compared to total population, once they start “taking it into account?”  The Court is not likely to answer that question and it will likely take years of litigation to sort it out.  But I think the most the Court would ultimately hold is that if states can do more to promote voter equality, while not allowing their districts to vary in total population by more than 10% and while not violating traditional districting principles, then within those constraints, states would need to avoid unnecessary departures from voter equality.  That is a long way away from a requirement that districts be based on voter equality — as a practical matter, even if there is a majority for the position Justice Kennedy was debating, I think the practical effect would be very modest changes in outcomes concerning how districts are designed and how the distribution of political power is affected.
6. The most important effect of Evenwel is not, therefore, likely to be doctrinal.  The case itself — as is often true of Supreme Court cases — raises the visibility of an option that many jurisdictions might well not have considered before.  Redistricters have been routinely using the Census data, which is total population data.  In some areas where the politics over immigration are particularly heated, some states or local government bodies might now start talking about shifting to CVAP data in the next redistricting cycle.  Will the litigation itself become a catalyst for some states to choose of their own accord to start districting based on voter equality, rather than total population — even if the Court’s decision does nothing more than affirm the status quo, in which this option has always been possible. That is the most politically consequential question surrounding this case, given that the Court is not going to hold that districting based on voter equality is constitutionally required.