Factual update and speculation… To speculate first, Scalia offered an unhappy announcement of his dissent in the Affordable Care Act decision, which I think may provide a spoiler on the outcome of the Congressional redistricting case. The ACA issue was statutory interpretation, and the majority read insurance exchanges “established by the state” to include ones established by the federal government in stead of the state. To bash this, Scalia referenced the Constitution’s elections clause, and suggested that everyone would agree that Congress using its election-regulating power would not represent “the state legislature” acting (this is from memory, but that’s the gist). So — if this means that the majority of the Court has agreed that a plain and un-nuanced reading of the elections clause is what commands, then I think the Independent Redistricting Commission is about to lose… (See the bullets below if you need a refresher on what that case is about.) It’s possible that he was forecasting another dissent in that case, but that’s not how I heard it.
Further speculation is that I expect we’ll know about that case tomorrow, with marriage on Monday. I say this simply because it seemed like redistricting is almost ready, and because both Kennedy and Roberts had major opinions today so are a little less likely to have opinions tomorrow (and they seem the most likely authors of a marriage decision). But that’s a bit of a stretch on my part, and I plan to be in the courtroom tomorrow in any event.
If you plan to attend, know that the public area was full today but the bar section was not. There was also a fairly sizable set of demonstrators out front. 
The Obamacare supporters were chanting (they cleverly had stickers to modify their large signs, depending on the outcome), and I saw people who looked like they had been ready for a decision in the marriage cases. So even standing outside the courtroom can be a worthwhile experience on big decision days.
Now for objective information: after today’s decisions, there are now 5 cases that were heard this term but are still undecided, with two announcement days left on the Court’s calendar–tomorrow and Monday. So an updated recap of what remains (ordered by date of oral argument):
- Congressional redistricting by independent bodies, Arizona State Legislature v. Arizona Independent Redistricting Commission (argued March 2). Frustrated with political gamesmanship and claims of racial discrimination in the process of drawing Congressional districts, voters in Arizona amended the state constitution to empower an independent body to draw the districts. Interestingly, Congressional districts are never mentioned in the U.S. Constitution, but it does state that “times, places and manner of holding elections for Senators and Representatives, shall be prescribed in each state by the legislature thereof.” (Art. I § 4.) Arizona’s legislature seized upon this to challenge the AIRC. Certainly, most people would not call the AIRC “the legislature,” but arguably the phrase refers to any body that makes statutory laws, and a state constitution can vest the legislative power in one body, in a bicameral system, or broken up among multiple bodies with specially defined legislative functions. In addition to the question of whether the Constitution permits the people of Arizona to prescribe this system, the Court must decide whether the legislature has standing to bring this case.
- Role of cost-benefit analyses in EPA regulations, [3 cases] v. EPA (argued March 25). Important issues about what the EPA must consider when it regulates power plants. Fuller analysis is here.
- Criminal law, Johnson v. US (argued April 20): (1) Whether mere possession of a short-barreled shotgun should be treated as a violent felony under the Armed Career Criminal Act. (2) Whether the residual clause in the Armed Career Criminal Act is unconstitutionally vague.
- Same-sex marriage, Obergefell v. Hodges (argued April 28). One of the most high-profile cases of the term.
- Death penalty drugs, Glossip v. Gross (argued April 29). A challenge to the “three-drug cocktail” commonly used in executions.