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A law professor investigates the legal decision to regulate U.S. greenhouse gases

The Rule of Five: Making Climate History at the Supreme Court

Richard J. Lazarus
Harvard University Press
368 pp.
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The U.S. Supreme Court’s 2007 decision in Massachusetts v. Environmental Protection Agency is widely seen as the most important U.S. environmental ruling of all time. But the suit, which led to a ruling that the Clean Air Act of 1970 empowered the U.S. Environmental Protection Agency (EPA) to regulate greenhouse gases, was almost never brought. Richard J. Lazarus’s wonderful new book, The Rule of Five, is the inside story of how this case came to be, how its lawyers struggled and fought over theories and roles, and how the late Justice John Paul Stevens patched together the five votes needed to secure a majority.

Lazarus is ideally suited to tell this story. A law professor at Harvard, he has represented the government and environmental groups in 40 Supreme Court cases and presented oral argument in 14. He also roomed with John Roberts during law school, and they later taught a course on the history of the Supreme Court together. For this project, he interviewed almost everyone involved in the case, including several of the judges and justices and (with their permission) their law clerks, and had access to internal memos and drafts of opinions.

The case in question was the brainchild of Joe Mendelson, a lawyer working for a little-known environmental group in Washington, D.C., called the International Center for Technology Assessment. In 1998, he drafted a 35-page petition to the EPA, arguing that it was the agency’s responsibility to regulate carbon dioxide and other greenhouse gases as pollutants, and put it in a drawer, awaiting the right time to file. A year later he decided that the time had come, but leaders of other environmental organizations pleaded and then pressured him not to file, thinking it would be better to wait for the expected ascension of a climate champion, Vice President Al Gore, to the presidency in January 2001. Mendelson filed anyway.

The EPA sat on the petition until after the November 2000 election. When George W. Bush took office, the agency’s newly instated political appointees fumbled the response in a way that made it easier to challenge in court. In 2013, 30 parties filed suits in the U.S. Court of Appeals for the District of Columbia, but the court dismissed them in a 2-to-1 split.

There are always long odds when one seeks to persuade the Supreme Court to take a case, but they are even longer when a side has legions of squabbling lawyers with different legal theories and just one chance to file a brief. But Lisa Heinzerling, a professor at Georgetown Law School, wrote what all agreed was a brilliant brief on behalf of the petitioners, and—to everyone’s shock—the Supreme Court took the case. Then began the fight over who would get to argue it.

This honor ultimately fell to James Milkey, a lawyer in the Massachusetts Attorney General’s Office who had never argued before the Supreme Court. As they had done with Mendelson, many other lawyers working on the case tried to get Milkey to step aside, claiming that he was not up to the task. But Milkey persisted, and—with the help of additional brilliant briefs led by Heinzerling—on argument day, he shone. In the months that followed, Justice Stevens found ways to persuade his colleague Anthony Kennedy to give him the crucial fifth vote needed to prevail.

Lazarus walks readers through all of the procedural steps and legal theories that surrounded this case, using lucid prose that is easy for nonlawyers to follow. The book is a master class in how the Supreme Court works and, more broadly, how major cases navigate through the legal system.

The Massachusetts v. EPA decision was the basis for almost all of the Obama administration’s actions on climate change, which included stricter regulations of emissions from motor vehicles and power plants. These actions, in turn, gave President Obama the legitimacy to press fellow world leaders to reach a landmark agreement on climate change in Paris in December 2015. However, in February 2016, the Supreme Court put Obama’s Clean Power Plan on hold, and President Trump has pressed to repeal it, to weaken the motor vehicle rule, and to pull the United States out of the Paris Agreement. As Lazarus rightly concludes, the most important legal decisions are made not in the courtroom, but at the ballot box.

About the author

The reviewer is at the Sabin Center for Climate Change Law, Columbia Law School, New York, NY 10027, USA, and is the co-editor of Legal Pathways to Deep Decarbonization in the United States (Environmental Law Institute, 2019).