Since early in the Trump administration, environmental policy has been a divisive topic, pitting manufacturers against environmentalists, regulators against businesses, and, it seems, coastal areas against the Midwest and South. This was particularly evident when several California cities, including San Francisco and Oakland filed suits against major energy companies. They were soon joined by New York City. In April, 15 state attorneys general filed an amicus brief supporting the energy companies in the California lawsuit. On Thursday, they gave their support to the targets of the New York lawsuit as well.

“The questions of global climate change and its effects—and the proper balance of regulatory and commercial activity—are political questions not suited for resolution by any court. Indeed, such judicial resolution would trample Congress’s carefully-calibrated process of cooperative federalism where States work in tandem with EPA to administer the federal Clean Air Act,” the attorneys general state in the brief.

The amicus brief was signed by the attorneys general of Indiana, Alabama, Arkansas, Colorado, Georgia, Kansas, Louisiana, Nebraska, Oklahoma, South Carolina, Texas, Utah, West Virginia, Wisconsin and Wyoming. These same officials had signed the previous brief.

The brief shows continuing support for BP, Chevron, ConocoPhillips, Exxon Mobil, and Royal Dutch Shell, the companies targeted by New York City’s lawsuit. Although some of the attorneys general represent states with vibrant energy industries, including Louisiana and Texas, others represent manufacturing hubs. Both of these sectors are concerned that rulings against the energy companies in either the New York or California lawsuits could have implications on environmental regulation in other states, with the potential to harm their economies.

“[The city lawsuits] are nothing more than a form of regulatory enforcement and creation of policy through the use of judicial remedies,” the attorneys general write in the amicus brief.

“[The] Plaintiff seeks to inject its political and policy opinions into the national regulatory scheme of energy production, promotion, and use. Yet all States play a critical regulatory role within their borders, and Congress has leveraged and augmented that authority by way of the Clean Air Act, a cooperative federalist program designed to permit each State to achieve its optimal balance of regulation and commercial activity.”

In their brief, the attorneys general argue that the lawsuits undermine the principle of cooperative federalism in which the federal government set overarching policy goals and leaves the details of implementation to the states. According to them, this is a recognition that the regulation of environmental standards is an “inherently political undertaking.”

They also push back on the common law arguments that the city’s case rests on. New York City’s lawsuit argues that greenhouse gas emissions fall under the category of nuisance and can be regulated under Common Law. However, the attorneys general argue that federal regulations, and specifically the Clean Air Act, have “displaced” the Common Law in this instance.

“The Supreme Court held more than seven years ago in AEP that Congress, by ‘delegat[ing] to EPA the decision whether and how to regulate carbon-dioxide emissions,’ had ‘displace[d] federal common law,'” they wrote.

As a result, the city’s argument is fundamentally flawed and they would be unable to to receive relief from the court.

The brief has been welcomed by manufacturing industry groups, who have been concerned that the city lawsuits could have regulatory impacts that reach across state borders.

“Once again, 15 state attorneys general have joined together in defense of manufacturers across the nation as trial lawyers continue to file misguided lawsuits,” said Lindsey de la Torre, executive director of the Manufacturers’ Accountability Project (MAP). “With continued support from the attorneys general, manufacturers can focus their efforts on solutions rather than fighting litigation that legal precedent has demonstrated will ultimately fail.”

New York City’s lawsuit against the energy companies has been ongoing since January. At this stage, it is uncertain how long they will continue.

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