Joe Mendelson didn’t seem like the kind of person who would upend the entire environmental movement in pursuit of a legal strategy to attack climate change. In 1999, he was a young public interest lawyer working at an obscure organization, the International Center for Technology Assessment. But, bucking the conventional wisdom of bigger environmental groups, Mendelson took the momentous step of filing the petition that led to the groundbreaking Supreme Court ruling in Massachusetts v. United States Environmental Protection Agency. 

That landmark 2007 decision—which has been described as the most significant environmental case in U.S. history—pushed the EPA to regulate carbon dioxide under the Clean Air Act. That gave advocates a mechanism to force a recalcitrant government to address climate change.

The Clean Air Act, signed into law by President Richard Nixon in 1970, requires the EPA administrator to regulate “emissions of any air pollutant” from new motor vehicles that contribute to “air pollution which may reasonably be anticipated to endanger public health or welfare.” Mendelson’s petition argued that carbon dioxide fit these criteria. The upshot: The EPA must regulate it. 

In his gripping new book, The Rule of Five, Richard J. Lazarus, a law professor at Harvard University, weaves the tale of how Mendelson’s petition led to the landmark decision, how he brought along the other environmental advocates despite bitter infighting, and how missteps by their opponents gave the lawsuit wings. Lazarus, who interviewed participants in the case, from lawyers to Supreme Court justices, writes like a novelist. Discussions of the so-called Chevron doctrine and “parts per billion” go down easy, enhancing the narrative rather than interrupting the flow.