The plaintiff satisfied the commonality requirement of Federal Rule 23(a)(2) by identifying common questions, the truth or falsity of which would "resolve an issue that is central to the validity of each claim in one stroke":
(i) whether class members generally worked overtime without receiving compensation as a result of Defendant’s unofficial policy of discouraging reporting of such overtime, Defendant’s failure to reduce class members’ workload after the reclassification, and Defendant’s policy of treating their pay as salaries for which overtime was an “exception”; (ii) whether Defendant knew or should have known that class members did so; and (iii) whether Defendant stood idly by without compensating class members for such overtime.These common questions constituted the "glue" necessary to say that "examination of all the class members’ claims for relief will produce a common answer to the crucial question[s]" raised by the plaintiffs’ complaint. Slip op. at 7-11.
The plaintiff could use statistical sampling and representative testimony to prove liability, "so long as the use of these techniques is not expanded into the realm of damages." The district court "was careful to preserve Allstate’s opportunity to raise any individualized defense it might have at the damages phase of the proceedings" and "preserved the rights of Allstate to present its damages defenses on an individual basis." As a result, the district court did not err by certifying the class. Slip op. at 11-15.
The opinion is available here.