In Smentek v. Dart, ___ F.3d ___ (7th Cir. Jun. 19, 2012), the Seventh Circuit (Judge Posner) construed the U.S. Supreme Court's opinion last year in Smith v. Bayer Corp., 131 S. Ct. 2368 (2011). The question considered was whether, under Smith, federal judges must afford "comity" to each other's orders denying class certification. The answer was no:
Whatever the scope of the Supreme Court’s current concept of comity, the defendants’ argument that Smith v. Bayer Corp. adopted a rule of comity in class action suits that precludes granting class certification in a copycat class action must be rejected ....
The rule urged by the defendants in this case that the denial of class certification bars the certification of the same or a similar class in a suit by a member of the same class as the previous suit ... would contradict the holding of Smith v. Bayer Corp., which is that a class member who did not become a party to the previous parallel class action is not precluded from seeking class certification in his class action. ....
We are left with the weak notion of “comity” as requiring a court to pay respectful attention to the decision of another judge in a materially identical case, but no more than that even if it is a judge of the same court or a judge of a different court within the same judiciary. We emphasize, however, the qualification in “materially identical.” Even two class actions involving the same class may differ materially, for example in the suitability of the class representative or the adequacy of class counsel, and where they do the judge in the second, or third, or nth class action is on his own. This is not such a case; nevertheless the district judge gave plausible reasons for her disagreement with the judges in the two previous Cook County dental cases. Can more be required? The defendants’ claim that she was bound by the decisions of the other judges just because those decisions preceded and were contrary to her decision has no basis in law and flouts the principle that a district court decision does not have precedential effect. Camreta v. Greene, 131 S. Ct. 2020, 2033 n. 7 (2011); Wirtz v. City of South Bend, 669 F.3d 860, 862-63 (7th Cir. 2012). The defendants would have such decisions treated not as mere precedents but as super-precedents that no court lacking appellate authority could question.
The district judge’s grant of class certification is therefore affirmed.
Slip op. at 6, 7, 8-9 (emphasis added).