Playing The Percentages
Did you know there was a statistic for appeals court judges? Yeah, you can actually separate the wheat from the chaff based on the all-important, revealing statistic of the reversal rate. This is clearly as crucial a stat in the American psyche as the RBI or free throw percentage. Divide the percentage of cases written by an appeals court judge overturned by the Supreme Court by the cases written by that judge taken up by the Court. A low reversal rate, under this stat, means a solid judge, while a high reversal rate means they are simply awful.
Depending on how much you want to stretch the truth, Sonia Sotomayor has a 90%, 80% or 50% reversal rate. Now, this statistic, which apparently is the only thing you have to know about any appeals court judge - it's on the back of their trading card - neglects the hundreds of opinions Sotomayor wrote or participated in that WERE NOT TAKEN UP BY THE SUPREME COURT. So maybe Nate Silver will come up with some alternative statistic, a "true reversal rate," which in Sotomayor's case would be less than one percent. Also, the average reversal rate for any case SCOTUS takes up is around 61% (activist judges!), putting Sotomayor below that bar even under the completely misleading standard of the statistic.
I'm pretty sure I never heard about John Roberts' or Samuel Alito's reversal rate. But the right has discussed Sotomayor's as if she's a free agent utility infielder with a lifetime .228 batting average. They've just invented the "reversal rate" as a meaningful reflection of judicial ability, and massively distorted the statistic to set those needs, besides. And by and large, media types allow this to go unchallenged.
Others may think that the best way to understand Sotomayor's judicial philosophy would be through, you know, reading her opinions. There you find a portrait of a judge who is deliberative and mostly consistent in following the law.
But why deal with all that "reading" when you can just reduce an entire legal career to a percentage?
...from biggerbox in the comments: "You don't understand - when a white male judge is reversed, that's merely an example of competent legal minds disagreeing about fine points of the law. When a Latina judge is reversed, that shows she's a dumb girl who doesn't know what the hell she is doing pretending to be a judge. What could be clearer?"