BOTH SIDES DO IT! (THOUGH ONE SIDE DOES IT MUCH MORE)

A study of Supreme Court rulings on speech yields this headline in The New York Times:

"In Justices’ Votes, Free Speech Often Means 'Speech I Agree With.'"

Notice that this is presented as a general principle that applies across the ideological spectrum:

... In cases raising First Amendment claims, a new study found, Justice Scalia voted to uphold the free speech rights of conservative speakers at more than triple the rate of liberal ones. In 161 cases from 1986, when he joined the court, to 2011, he voted in favor of conservative speakers 65 percent of the time and liberal ones 21 percent.

He is not alone. "While liberal justices are over all more supportive of free speech claims than conservative justices," the study found, "the votes of both liberal and conservative justices tend to reflect their preferences toward the ideological groupings of the speaker."

Yes, but among current and recently retired justices, the votes of the conservatives are far more biased in favor of conservative speakers than the votes of liberal justices are in favor of liberal speakers. The Times gives us a bar graph (excluding Justices Kagan and Sotomayor, who don't have a sufficiently extensive record to measure). We're told that the key point is that "both conservative and liberal justices are more likely to vote in support of speakers if they share their ideology." But look at the skews:





Or in numerical form, from the original paper (PDF):

For Thomas, Scalia, Alito, and Roberts, the gap is massive. Even Kennedy is a third more likely to back a conservative speaker than a liberal one. For Ginsberg, the gap isn't nearly as large, and for Breyer there's barely a gap at all.

The Times story, by Adam Liptak, sets out to explain what's going on:

Social science calls this kind of thing "in-group bias." The impact of such bias on judicial behavior has not been explored in much detail, though earlier studies have found that female appeals court judges are more likely to vote for plaintiffs in sexual harassment and sex discrimination suits.

Lee Epstein, a political scientist and law professor who conducted the new study with two colleagues, said it showed the justices to be "opportunistic free speech advocates."

Yes, but ... isn't one side a tad more "opportunistic" than the other? Could you just say that?

Nope:

The largest [gap], at least among members of the Supreme Court who cast more than 100 votes in free speech cases since 1953, belongs to Justice Scalia. Justice Clarence Thomas is not far behind. Chief Justice John G. Roberts Jr. and Justice Samuel A. Alito Jr. have not cast enough votes for a reliable appraisal, but the preliminary data show a similarly significant preference for conservative speakers.

Justice Anthony M. Kennedy, the current court's most reliable free speech vote, favored conservative speakers by a smaller but still significant margin.

The Roberts court's more liberal members "present a more complex story," the study found. All supported free expression more often when the speaker was liberal, but the results were statistically significant only for Justice John Paul Stevens, who retired in 2010.

In the case of Justice Stephen G. Breyer, the difference was negligible. And it is too soon to say anything empirically meaningful about Justices Sonia Sotomayor and Elena Kagan.

Um, is that "a more complex story"? It seems fairly simple to me: the more liberal justices show a modest liberal bias, while the four dyed-in-the-wool conservatives are unabashedly biased toward their side. There's no comparison.

So why not say so in plain English?