On March 18, the Supreme Court declined to review a Sixth Circuit decision affirming an Ohio federal court’s order certifying a class on specific issues in a groundwater pollution suit.

• In 2008, residents of the McCook Field neighborhood in Dayton, Ohio sued four corporate defendants for allegedly contaminating the groundwater beneath their properties. 
• The plaintiffs sought certification under Rule 23(b)(3), which requires plaintiffs to show, among other things, that “questions of law or fact common to class members predominate over any questions affecting only individual members.”  Alternatively, they sought certification under Rule 23(c)(4), which provides that “[w]hen appropriate, an action may be brought or maintained as a class action with respect to particular issues.”
• The district court rejected class certification under Rule 23(b)(3) on the basis that the plaintiffs could not satisfy the predominance requirement, but certified seven “common” issues under Rule 23(c)(4), such as questions concerning each defendant’s role in creating the contamination, whether the defendants engaged in abnormally dangerous activities, and the foreseeability of subsequent injuries.
• Importantly, the court held that a plaintiff seeking issue certification under Rule 23(c)(4) need not show that the entire action could satisfy Rule 23(b)(3)’s predominance requirement. 
• The Sixth Circuit unanimously affirmed, agreeing with the Second, Fourth, Seventh and Ninth Circuits’ “broad” view of the predominance requirement.  The Sixth Circuit appeared to go one step further than the other circuits in allowing issue class certification despite individualized issues of causation, injury, and damages, noting that the resolution of the plaintiffs’ seven “common” issues would materially advance the litigation. 
• By contrast, under the “narrow” approach adopted by the Fifth Circuit in Castano v. American Tobacco Company, and largely endorsed by the Eleventh Circuit, a district court “cannot manufacture predominance through the nimble use of subdivision (c)(4),” which is merely “a housekeeping rule that allows courts to sever the common issues for a class trial.”  Other circuits—such as the Third and Eighth Circuits—have declined to adopt either position, opting instead for more functional, efficiency-based approaches.
• The Sixth Circuit’s decision, and the Supreme Court’s decision not to intervene, may inspire more plaintiffs to pursue Rule 23(c)(4) issue classes in toxic tort cases.  Defendants can combat such efforts by developing a factual record demonstrating that individualized inquiries overwhelm common questions within each Rule 23(c)(4) issue, and by arguing that the necessity of separate proceedings to resolve key individual issues such as causation, injury, and damages precludes plaintiffs’ ability to show that certifying a Rule 23(c)(4) class would materially advance the litigation.