The Ninth Circuit Court of Appeals recently addressed the question of class certification for commonality of a claim in Stockwell v. City & County of San Francisco. This case involved the use of promotional performance exams within the police department. In 1998, the city administered a promotional performance exam ranking officers. Again in 2005, although the officers were still ranked under the prior exam, the city changed policy and administered a different exam. The officers claimed that the change had a disparate discriminatory impact based on the age of the officers and brought suit under the FHDA and the ADEA. The district court denied class certification, holding the case meritless. The officers sought an interlocutory appeal under Fed. R. Civ. P. 23(f) for denial of class certification. The court held that questions of commonality are separate from the merits of the claim. An assessment of commonality is determined by whether the “putative class members share a common question, the answer to which will resolve an issue that is central to the validity of each of the class member’s claims.” Although the court sometimes will be unable to address the commonality and the merits of the claim separately, the merits are to be addressed at trial or on motion for summary judgment. The fact that the class claim will fail on the merits does not defeat the existence of a common question that is capable of classwide resolution. After finding that the officers had met the requirements for a disparate-impact age discrimination claim the Ninth Circuit reversed the denial of class certification and remanded the case to the district court. The claim as to whether the change in policy had a disparate impact on age, whether meritless or not, could not justify the denial of class certification for lack of commonality.