FantasySCOTUS Predictions Before, During, and After Oral Arguments in King v. Burwell

FiveThirtyEight continues to mine the FantasySCOTUS dataset for insights into Supreme Court forecasts. The latest feature offers insights into how the predictions for the Court–Chief Justice Roberts and Justice Kennedy–fluctuated throughout leading up to, during, and after oral arguments as reports leaked out:

Here are the shifts in the predictions over the course of the past few days. The plot represents a rolling average of the last 200 predictions entered by FantasySCOTUS players. The proportion of predicted votes to strike a blow to the ACA fell sharply Wednesday. …

Roberts was seen as significantly less likely to vote against maintaining the ACA than he was before oral argument. Kennedy, another swing vote, also came away seeming less likely to vote against the ACA.

Despite the shifts on King v. Burwell, the outcome is still up in the air. Josh Blackman, FantasySCOTUS’s creator, told me: “Going into arguments, I thought the case was a tossup. Leaving arguments, I still think the case is a tossup. And it looks like the players of FantasySCOTUS agree: It is a tossup.”


Scalia 91% 93%
Thomas 90 92
Alito 88 91
Kennedy 66 50
Roberts 53 43
Ginsburg 17 12
Sotomayor 17 12
Breyer 17 11
Kagan 16