Last week, the Ninth Circuit in NRDC v. County of Los Angeles ruled that the government defendants were liable for Clean Water Act violations because pollutant levels at various monitoring stations in the Los Angeles area exceeded what was allowed under the defendants’ stormwater permits. Earlier this year the Supreme Court overturned the Ninth Circuit’s earlier decision upholding liability on another basis. At that time, I had predicted that the Ninth Circuit on remand would likely rule in favor of the defendants, because the alternative theory of liability that the plaintiffs had advanced the Ninth Circuit had already rejected. Yet, surprisingly, the Ninth Circuit on remand reconsidered its earlier decision. Legally, the Ninth Circuit has that power, but it’s disappointing that the court did not at least explain why it found this alternative theory correct now on remand. That is particularly so given the impact of the court’s remand decision. Now, one can be liable for Clean Water Act violations simply because one has exceeded permit monitoring standards, regardless of whether those exceedances would independently constitute a violation of the Act. This rule will create a perverse incentive for permit applicants to negotiate fewer rather than more monitoring stations. I would not be surprised to see a petition for rehearing en banc, or another cert petition.