A Slate piece, “Sotomayor’s Manly Man Ruling – Her bold ruling in favor of a man who claimed sex discrimination,” by Emily Bazelon, includes this paragraph on unpublished opinions:
Sotomayor agreed to issue an unsigned and unpublished opinion. The term “unpublished opinion” is a bit of a misnomer. These rulings appear in the Lexis and Westlaw databases, where lawyers do legal research. And since a change in the rules in 2007, lawyers have been able to cite unpublished opinions in other cases. But unpublished opinions have second-class status. They’re shorter and often still carry less weight–they’re persuasive rather than binding precedent, in lawyer’s terms. They are not supposed to be the way judges dispose of difficult cases that raise substantive or novel legal issues. But sometimes those cases sneak in, because once a culture of unpublished opinions takes hold in a particular circuit, it’s hard to control. And in the 2nd Circuit, I’m told, there’s a premium on unanimity and consensus, so a 3-0 unpublished opinion might trump a 2-1 published one, in some cases and in some judges’ eyes.