They Knew

They Knew

The US Federal Government's Fifty-Year Role in Causing the Climate Crisis

By James Gustave Speth

Introduction by Julia Olson and Philip Gregory

A devastating, compelling account of the federal government's leading role in bringing about today's climate crisis.





A devastating, compelling account of the federal government's leading role in bringing about today's climate crisis.

In 2015, a group of twenty-one young people sued the federal government in Juliana v. United States for violating their constitutional rights by promoting climate catastrophe and thereby depriving them of life, liberty, and property without due process and equal protection of law. They Knew offers evidence supporting the children's claims, presenting a devastating and compelling account of the federal government's role in bringing about today's climate crisis. James Gustave Speth, tapped by the plaintiffs as one of twenty-one preeminent experts in their climate case, analyzes how administrations from Carter to Trump—despite having information about the impending climate crisis and the connection to fossil fuels—continued aggressive support of a fossil fuel based energy system.

What did the federal government know and when did it know it? Speth asks, echoing another famous cover-up. What did the federal government actively do and what did it fail to do? They Knew (an updated version of the Expert Report Speth prepared for the lawsuit) presents the most definitive indictment yet of the US government's role in the climate crisis.

Since Juliana v. United States was filed, the federal government has repeatedly taken unprecedented steps to delay the case and force it to the appellate courts' shadow dockets. Yet as the case progresses slowly but certainly, it is inspiring a generation of youthful climate activists.

An Our Children's Trust Book


$27.95 T ISBN: 9780262542982 304 pp. | 6 in x 9 in 21 b&w illus.

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$19.95 T ISBN: 9780262545099 304 pp. | 6 in x 9 in 21 b&w illus.


Julia Olson and Philip Gregory.


  • A rousing condemnation of a system bent on short-term gain against long-term health.

    Kirkus Reviews

  • Drawing on first-hand knowledge from his time as chair of the US Council on Environmental Quality during the administration of president Jimmy Carter (1977–81), and his founding role in several major environmental non-governmental organizations, Speth gives a clear and concise account of the scientific evidence available to successive US presidents and Congresses over five decades. He provides a chilling description of the gulf between the safer course of action recommended by scientists and advisers, and the reality of federal policy.


  • Working pro bono [for Juliana v. United States], Speth produced a lengthy report tracing nearly 60 years of federal action on climate change and fossil fuel development. That report is the foundation for this book. Parts of the story have been told before... but Speth's volume covers a broader period of time, says more about federal encouragement of fossil fuels, and as befits a legal filing, is richly documented.


  • Gus Speth's new book is an enlightening and infuriating academic masterpiece, a detailed history of the US federal actions and inactions on climate change, a biting indictment and fascinating read.

    Udo E. Simonis

    Journal of Environmental Law and Policy

  • They Knew is a must-read, because this book is not so much 'history' as it is a window into the present, in which the pressures from the fossil fuel industry and the processes of government collide. The more we can see what they knew then, the greater the possibility that we can contend with what we know now.

    YES! Magazine

  • The road to climate hell has long been paved with deniability. While climate scientists over the past half century have amassed evidence that the use of fossil fuels is bringing about environmental disaster, US presidents and congresses have been steadfast in looking the other way. The publication of this well-researched, damning examination and indictment of federal policies will make it impossible to assert ignorance ever again.

    Yale Alumni Magazine


  • “Devastating. Enraging. Indispensable. Would that the world had more heroic elders like Gus Speth. He has produced a damning record that will become a potent tool for justice.”

    Naomi Klein

    Gloria Steinem Chair in Media, Culture, and Feminist Studies at Rutgers University; author of This Changes Everything, The Shock Doctrine, and No Logo

  • “With skill and dedication, Gus Speth has documented precisely what we knew and when we knew it. This book is a shocking reminder of the chances for action we've already missed, and a spur to finally move with the vigor the climate crisis demands.”

    Bill McKibben

    Schumann Distinguished Scholar in Environmental Studies at Middlebury College; founder,

  • “Wondering how in the world the catastrophe of climate change could be happening and whom to hold responsible? Look no further than They Knew—Gus Speth's enlightening and infuriating new book.”

    Van Jones


  • “Gus Speth has written a history of federal action and inaction on climate change that spares neither Democrats nor Republicans. They Knew is at once a searing indictment and a fascinating read.”

    Elizabeth Kolbert

    staff writer, New Yorker; author of Under a White Sky and The Sixth Extinction

  • “Speth reveals the smoking gun of the climate crisis in the US government's unholy alliance with the fossil fuel industry. The history presented in They Knew makes clear that democratic action is needed now to ensure a future for seven generations to come.”

    Catherine Flowers

    Founder and Director, Center for Rural Enterprise and Environmental Justice; Professor of Practice, Duke University; 2020 MacArthur Fellow; author of Waste