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Many observers believe the Supreme Court’s Twombly and Iqbal opinions have curtailed access to civil justice. But previous empirical studies looking only at Rule 12(b)(6) grant rates have failed to capture the full effect of these cases because they have not accounted for party selection—changes in party behavior that can be expected following changes in pleading standards. In this Note, I show how party selection can be expected to undermine the empirical usefulness of simple grant-rate comparisons. I then use a conceptual model of party behavior that allows me to derive an adjusted measure of Twombly/Iqbal’s impact and show how to estimate a lower bound on this measure using data from recent studies by the Federal Judicial Center. My empirical results suggest that, depending on the nature of the suit in question, Twombly and Iqbal have negatively affected plaintiffs in at least 15% to 21% of cases that faced Rule 12(b)(6) motions in the post-Iqbal data window. Again depending on the nature of the suit, these figures represent between one-fourth and two-fifths of the cases that fail to reach discovery on at least some claims in the post-Iqbal data window.


Litigation, Civil Law and Procedure, Antitrust Law, Judges

Publication Title

Yale Law Journal

Publication Citation

121 Yale L. J. 2270 (2012).