Did The 5th Circuit Just Make Standing Much More Difficult?

Last week, the 5^th Circuit Court of Appeals vacated a $20M penalty imposed on ExxonMobil for Clean Air Act violations at its Baytown facility, remanding the case for a more particularized review by the District Court regarding whether the plaintiffs have demonstrated that they have standing with respect to all of the violations committed by ExxonMobil. The Court held that it is not enough to show that each of the claims in the complaint are traceable to ExxonMobil's conduct. Instead, the plaintiffs must demonstrate that they have suffered harm traceable to the violations committed by ExxonMobil.

As an initial matter, I think that the Court erred when it rejected the plaintiffs argument that the law of the case precluded the court from reexamining standing. In the first go-round, the District Court declined to impose a penalty and 5^th Circuit reversed. This time around, the plaintiffs pointed out that, since standing is jurisdictional, the prior 5^th Circuit panel