Oren Cass

Oren Cass


  • JD, Harvard University (2012). [1]
  • BA, Political Economy, Williams College (2005). [1]


Oren Cass is a senior fellow at the Manhattan Institute (MI). According to his profile, Cass promotes “conservative policy approaches on poverty, climate change, environmental regulation, and international trade.” He regularly writes policy reports for MI on issues including climate change. [2]

Cass was domestic policy director for Mitt Romney’s presidential campaign from 2011 to 2012, where he regularly attended debates at Harvard University and MIT on issues like health care, energy, and environmental policy. [2]

Oren has made regular presentations at conferences including those of the Manhattan Institute, the Legatum Institute, the American Enterprise Institute, the Cato Institute, the Adam Smith Society, the Conservative Policy Action Conference, the American Legislative Exchange Council, and the State Policy Network. [3]

Before joining MI, Cass worked for the Boston and New Delhi office of Bain & Company as a management consultant. [2]

Stance on Climate Change

January 1, 2017

Cass wrote in National Affairs: [4]

“The scientific consensus holds that the climate is warming and human activity plays a substantial role. But there is no consensus about how much warming human activity has caused or will cause.”


“[W]hile extreme climate change is a quintessentially worrying problem, it is also one that has no guarantee or even likelihood of occurring. Certainly, the ‘scientific consensus’ or even the ‘scientific mainstream’ on climate change does not extend to confidence in such scenarios.

“To compare extreme climate change with other worrying problems, it is helpful to consider the dimensions that make a problem ‘worrying’: that it is forecasted, irreversible, and pervasive. On all three, climate change appears less worrying than most.”

December 1, 2016

“There is a consensus among climate scientists that human activity is contributing to climate change. However, claims that rising temperatures pose an existential threat to the human race or modern civilization are not well supported by climate science or economics; to the contrary, they are every bit as far from the mainstream as claims that climate change is not occurring or that it will be beneficial. Analyses consistently show that the costs of climate change are real but manageable. For instance, the prosperity that the world might achieve in 2100 without climate change may instead be delayed until 2102,” Cass wrote in a Manhattan Institute “Issue Brief” titled “Climate Costs in Context.” [5]

October 3, 2016

Referring to a pro-carbon-tax article at the Wall Street Journal, Cass wrote at the National Review Online: [6]

“I am convinced by the scientific consensus on climate change, but I would still slam the door in the face of anyone who came to me with that offer. If an insurance salesman promises his policy is not-too-expensive but tells you nothing concrete about the benefits, walk away quickly.” [6]

March 5, 2013

Writing at The National Review, Cass agreed that there is a scientific consensus on climate change. However, he disagreed that emissions reductions are a solution: [7]

“Unless the scientific community is perpetrating an unprecedented hoax, the existence of such a widespread consensus indicates at least a significant likelihood of a real danger, which presents policymakers with an actual risk deserving of serious consideration.

Accepting the science does not, however, require one to accept the liberal policy prescriptions.  Science is only an input to any policy discussion, and nowhere is this truer than in the case of climate change, where the scientific consensus resolves remarkably little. More carbon in the atmosphere leads to warming, but how much warming? Scientists speak in terms of ‘climate sensitivity — how sensitive is the climate to some increase in carbon dioxide? Here there is very little agreement.” [7]

Cass also stated that “the threat of climate change is based on a ‘stock,’ not a ‘flow’,” suggesting that “Lower U.S. emissions do not ultimately reduce the threat of climate change; they simply postpone some portion of it.” [7]

Key Quotes

February 17, 2017

Cass celebrated Scott Pruitt‘s nomination to lead the Environmental Protection Agency (EPA), writing in the opinion section of the U.S. News and World Report: [8]

“Scott Pruitt is the ideal person to stop the agency’s overreach,” Cass wrote

“Perhaps if the nation were struggling with unprecedented pollution and seeking to implement new laws in response, an EPA Administrator who specialized in pollution control technology would be more appropriate. But that is not the case. As the EPA proclaims proudly, air pollution has declined 70 percent in the past 45 years. What the nation struggles with today is costly and unlawful overreach by its federal environmental agency. Pruitt can help to fix that.  [8]

May 2016

Speaking at the 2016 Conservative Political Action Conference, Cass said of leaders of developing countries, “no matter how seriously they take the science of climate change, are focused on economic [growth]. As long as that’s the case, we in the United States are just spitting into the wind.” [9]

December 19, 2016

“Even if President Trump reverses President Obama’s efforts, the marginal effect on future climate change will be minimal because Obama’s efforts were so inconsequential,” Cass wrote at the National Review. [10]

December 17, 2015

“If the topic of conversation is climate policy, conservatives should be winning. They will need to show endless patience in the face of ever more bizarre hyperbole — a Reaganesque ‘There you go again’ is probably about right. And they will need to confidently describe an affirmative policy agenda, preferably emphasizing research and development that might identify new technologies so cheap and clean that developing countries will want to use them along with tools for adapting to whatever climate change does bring,” Cass wrote at the National Review. [11]

November 28, 2015

“If you actually care about global warming, you should be rooting against an agreement,” Cass said of the Paris Climate Agreement in an article at Politico[12]

March 9, 2015

“The Clean Air Act, by virtue of decisions made and priorities chosen decades ago, is forcing Americans to accept substantial economic sacrifices that they cannot afford, in pursuit of environmental gains that they do not need and that are not worth the cost,” Cass wrote in a 2015 National Review article. 

”[…] Precisely because America has made so much environmental progress, a marginal investment in further economic growth now offers a far greater societal return than a marginal investment in further environmental quality.” [13] 

Key Deeds

May 8, 2018

A new set of documents released to the Natural Resource Defense Council (NRDCas part of a Freedom of Information Act (FOIA) request revealed details of Pruitt’s plan to engage in a “red team, blue team” expertise on climate change. The documents showed communications between the EPA and a number of corporate-funded conservative think tanks with views that run counter to established science on climate change including the Heartland Institute, the Manhattan Institute, and the CO2 Coalition[46]

Oren Cass was also included in EPA communications: [46]

 “We were thinking this meeting could be purely informative in nature, and not necessarily in the context of a specific EPA exercise,” Tate Bennett, associate administrator at the EPA wrote to Cass in a January 18 email. [46]

Cass later said that he believed past analysis used by the EPA regarding the economics to address climate change as flawed. “I encourage conservatives to accept mainstream climate science and focus on economic analysis and good public policy,” Cass said. [46]

March 2018

The Manhattan Institute announced a lecture and new report by Oren Cass. The lecture, titled “Overheated: How Flawed Analyses Overestimate The Costs Of Climate Change,” was originally scheduled for March 7, 2018, but was “cancelled due to anticipated inclement weather” with a new date set for March 20. [14][15][16]

What kind of disruptions should Americans anticipate from climate change? According to the studies that have informed federal policy, the scenario is dire: increased deaths from extreme heat and air pollution, as well as reduced economic productivity. In a groundbreaking new report, however, MI senior fellow Oren Cass argues that the situation is not nearly so grim,” the event description read, adding “the long-term costs of climate change are being consistently overstated while too little energy is being devoted to plans for adaptation.” [16]

Cass released the report on March 11, with an accompanying article in The Wall Street Journal titled “Doomsday Climate Scenarios Are a Joke.” In the WSJ article, Cass argued that estimates of the cost of climate change come from “laughably bad economics,” and that adaptation is the answer to climate-change related deaths. [42], [43]

“If you imagine society is static and incapable of innovation, the prospect of climate change must be terrifying,” Cass wrote at WSJ. He reiterated this focus in the conclusion of the full Manhattan Institute report: [44]

“[C]orrelation-based temperature-impact studies that produce very high estimates of the economic and social costs of projected climate change—meanwhile ignoring or downplaying the possibility of adaptation and obscuring the inaccuracy of underlying estimates—are distinctly unhelpful,” Cass concluded.

Skeptical Science has noted that the cost of preventing global warming is relatively cheap when compared to the accelerating costs of climate-change-related damages. With regards to adaptation, mass species extinctions of the past have also been strongly linked to climate change.

Cass presented his report on March 20, 2018: [45]

January 18, 2018

Cass appeared at an American Enterprise Institute (AEI) and Opportunity America event titled “This way up: New thinking about poverty and economic mobility.” According to the event summary, Cass argued for wage subsidies and “an ‘inverse payroll’ tax that would add a certain amount to low-income Americans’ paychecks.” [17]

May 1, 2017

Cass published an article in National Review titled “Climate-Change Activists Are the Real Science Deniers” which prompted a critique by John Cook, founder of Skeptical Science and research assistant professor at the Center for Climate Change Communication at George Mason University. [18], [19]

“It’s with some degree of irony that Cass quotes figures from our survey-of-surveys to cast doubt on the consensus. He employs the very technique we warn against by using samples including non-experts,” Cook wrote at National Review. Cook looks to a paper Cass cited to get an 82 percent consensus figure as an example. According to Cook, the 2009 paper by Peter Doran and Maggie Zimmermann surveyed scientists from a wide range of disciplines. However, “When Doran looked at scientists with the relevant expertise — climate scientists publishing climate research — he found 97 percent consensus.” [19]

In another article, Cass countered with his own criticism of Cook, and wrote “I fully accept mainstream science in my article.” [20]

In June, John Cook appeared with Cass in a two-part episode of the program Evidence Squared to discuss their interchange at The National Review. Audio below. [21], [22]

Part 1

Part 2

April 27, 2017

Cass wrote a MI report arguing in favor of cuts to the EPA. According to the report, “While environmental activists will always demand larger budgets and tighter standards, Americans can rest assured that they will continue to benefit from outstanding air quality in the years to come.” [23], [24]

“Clean air should be a priority for all Americans, but thankfully it has been achieved. Air pollution has declined more than 70% since the passage of the Clean Air Act in 1970; even this nation’s most crowded cities enjoy air quality far superior to that of European capitals. This progress has continued across Democratic and Republican administrations, EPA expansions and EPA cuts, aggressive federal action and delegation to states, and it will continue under a Trump administration as well,” Cass claimed. [24]

“[E]ven if the EPA has fewer enforcement resources, it is difficult to envision major emitters violating federal law by shifting back to outdated technologies. Perhaps the EPA will slow its development of new regulations, but those on the books already ensure continued progress through the heightened demands that they impose on new sources of pollution.” [24]

March 21, 2017

Cass wrote an article titled “The Problem With Climate Catastrophizing” in Foreign Affairs, where he argued that adaptation is an appropriate response to climate change. [25]

“The idea that humanity might prepare for and cope with climate change through adaptation is incompatible with catastrophists’ outlook,” Cass wrote. “Yet if the damage from climate damage can be managed, anticipating challenges through research and then investing in smart responses offers a more sensible path than blocking the construction of pipelines or subsidizing the construction of wind turbines. Catastrophists countenance progress only if it can be fueled without carbon-dioxide emissions. Yet given the choice, bringing electricity to those who need it better insulates them from any climate threat than does preventing the accompanying emissions.” [25]

Climate scientist Michael Mann responded to Cass’s article. He wrote that “rather than assessing the legitimate range of views regarding climate change, Cass marshals a series of fallacies in an apparent effort to justify a fossil fuel-friendly agenda of inaction.” Mann noted that, while Cass portrayed mainstream climate scientists as “catastrophists,” rather “scientists have been overly conservative in their assessments, tending to understate the actual threat posed by climate change—the very opposite of catastrophism. [26] 

Cass wrote another article responding to Mann’s, claiming that Mann did not refute his argument. [27]

April 2016

Cass wrote a MI report titled Who Pays the Bill for the Obama Climate Agenda?” claiming that “President Obama’s climate agenda represents an enormous tax increase on low- and middle income Americans, nearly tripling the federal tax burden on the poorest households.” [28]

[T]he policy pays only lip service to ‘action’ on climate change and will not affect the trajectory of global greenhouse-gas emissions or temperatures,” Cass wrote in the report. [29]

December 2016

Cass wrote a report outlining “Ideas for the New Administration” on energy and environment. The report listed “four steps that Congress and the new Trump administration can take” including a lessened focus on renewable energy: [30]

“Expedite permitting processes for energy infrastructure by establishing fixed timelines, assigning a single agency responsible for coordination, and deeming pipelines and export terminals as “in the national interest.”

2. Open more public lands and waters to natural-resource development and create a settled, reliable framework that encourages private investment.

3. Suspend New Source Performance Standards under the Clean Air Act, allowing industrial facilities to be built and expanded under the same standards that already apply to existing facilities.

4. Refocus climate policy away from wind and solar, toward more effective existing technologies and the development of new ones.” [30]

December 1, 2016

Cass wrote a MI report titled “Climate Costs in Context” claiming that the country is capable of adapting to climate change. While the costs “are substantial and have the potential to cause significant damage and disruption,” Cass claimed that “none are outside the range of other challenges facing society, and none support the apocalyptic rhetoric of many politicians and activists.” [5]

November 17, 2016

The Legatum Institute and Manhattan Institute partnered on a one-day conference on “the most important issues facing the next American Administration, and the related implications on the ‘Special Relationship’ with post-Brexit Britain.” The conference agenda listed Cass as a speaker on the topic of trade policy. [31]

July 27, 2016

Cass was a speaker at the American Legislative Exchange Council (ALEC) 2016 Annual Meeting in Indianapolis. [32]

According to the event agenda, Cass was a speaker at a workshop titled “A Balanced Discussion About Energy Policy in the Next Administration.” [33]

According to the Center for Media and Democracy, “ALEC is a pay-to-play operation where corporations buy a seat and a vote on ‘task forces’ to advance their legislative wish lists and can get a tax break for donations, effectively passing these lobbying costs on to taxpayers. [33]

December 1, 2015

Cass testified to the House Science Committee on the Paris Climate Deal: “My primary message to the committee is this: the climate policies pursued by this country under President Obama are a bad deal for the climate and a bad deal for this country,” Cass said in his testimony. [34]

November 18, 2015

Cass testified before the US Senate Environment and Public Works Committee, alleging that the United Nations Framework Convention on Climate Change (UNFCCC) “no longer bear a substantial relationship to the goal of sharply reducing greenhouse gas emissions” and that the “only likely achievement of the upcoming Paris conference (COP21) is a commitment by developed nations including the United States to transfer large sums of wealth to poorer nations.” [35]

October 30, 2015

Cass was a presenter at a Cato Institute Conference titled “Preparing for Paris: What to Expect from the U.N.’s 2015 Climate Change Conference.” He appeared on Panel 3 “Realistic Expectations from Paris.”  Attendees included many noted climate change deniers with the agenda listing Judith Curry, Richard Tol, Roy Spencer, Peter Glaser, and Chip Knappenberger among others. [36]

October 16, 2015

Oren Cass wrote the MI report “Leading Nowhere: The Futility and Farce of Global Climate Negotiations” suggesting that “no negotiated agreement will significantly reduce global emissions of CO2.” [37]

August 4, 2015

Cass opposed President Obama’s Clean Power Plan (CPP). In a statement, he described it as a “an illegal overreach that claims power never given to the E.P.A. and bullies both states and private businesses.” [38]

“Its primary effects will be to disrupt markets and drive up costs, handing victories to politically-favored ‘green’ industries and sending the bill to consumer,” Cass asserted. [38]

On August 4, 2015, Cass was a guest on the On Point radio show in Boston where he claimed that the CPP would have “no actual impact on climate change”: [39]

June 2015

Oren Cass appeared on Fox News to suggest that Liberals would use Pope Francis’s encyclical on the environment to “advance their political cause” and to ignore statements that condemn abortion: [40]

May 14, 2015

Writing at the Washington Examiner, Cass argued against the link between rising global temperatures and asthma, despite studies suggesting otherwise. [41]


Social Media


The Manhattan Institute maintains a list of Oren Cass’s latest publications, testimony, and reports[2]



MI Reports





  1. Oren Cass,LinkedIn. Accessed March 8, 2018.
  2. Oren Cass,” Manhattan Institute. Archived March 8, 2018. Archive.is URL: https://archive.is/IOrBy
  3. ABOUT OREN,” Orencass.com. Archived March 8, 2018. Archive.is URL: https://archive.is/fgpQW
  4. Oren Case. “How to Worry about Climate Change,” National Affairs, Number 34 (Winter 2018). Archive.is URL: https://archive.is/2VLCU
  5. “Climate Costs in Context” (PDF), Manhattan Institute, December 1, 2016.
  6. Oren Cass. “Don’t Buy This Climate Insurance Policy,” National Review Online, October 3, 2016. Archived March 8, 2018. Archive.is URL: https://archive.is/OlVor
  7. Oren Cass. “The Next Climate Debate,” National Review, March 5, 2013. Archived March 8, 2018. Archive.is URL: https://archive.is/bJELR
  8. Oren Cass. “An EPA That Knows Its Limits,” U.S. News & World Report, February 15, 2017.
  9. Okla. AG: ‘We must have another Justice Scalia’ to fight EPA,” E&E News, March 4, 2016. Archived March 8, 2018. Archive.is URLhttps://archive.is/C3Cm4
  10. Oren Case. “Trump the Climate-Slayer,” National Review, December 19, 2016. Archived March 8, 2018. Archive.is URLhttps://archive.is/nJsUA
  11. Oren Cass. “Climate Play-Acting,” National Review, December 31, 2015. Archived March 8, 2018. Archive.is URL: https://archive.is/sDHlQ
  12. Why the Paris climate deal is meaningless,” Politico, November 28, 2015. Archived March 8, 2018. Archive.is URLhttps://archive.is/tN9fT
  13. Oren Cass. “Reform the Clean Air Act,” National Review, March 9, 2015. Archived March 8, 2018.
  14. Overheated: How Flawed Analyses Overestimate The Costs Of Climate Change,” Manhattan Institute. Archived March 5, 2018. Archive.is URLhttps://archive.is/fwDyP
  15. Overheated: How Flawed Analyses Overestimate The Costs Of Climate Change,” Manhattan Institute. Archived March 7, 2018. Archive.is URLhttps://archive.is/nUDRA
  16. Overheated: How Flawed Analyses Overestimate The Costs Of Climate Change,” Manhattan Institute. Archived March 8, 2018. Archive.is URL: https://archive.is/FdvYd
  17. This way up: New thinking about poverty and economic mobility,” American Enterprise Institute, January 18, 2018. Archived March 8, 2018. Archive.is URL: https://archive.is/TkK9h
  18. Climate-Change Activists Are the Real Science Deniers,” National Review, May 1, 2017. Archived March 8, 2018. Archive.is URL: https://archive.is/WitaO
  19. John Cook. “How to Recognize ‘Science Denial’,” National Review, May 15, 2017. Archived March 8, 2018. Archive.is URLhttps://archive.is/wmpG6
  20. Oren Cass. “John Cook’s Leap of Faith,” National Review, May 15, 2017. Archived March 8, 2018. Archive.is URL: https://archive.is/XUOQ7
  21. EP 14: OREN CASS AND SCIENTIFIC CONSENSUS,” Evidence Squared, June 7, 2017. Archived .mp3 on file at DeSmog.
  22. EP 15: OREN CASS ON ALARMISM VS DENIAL,” Evidence Squared, June 22, 2017. Archived .mp3 on file at DeSmog.
  23. Oren Cass. “Will EPA Cuts Harm America’s Air Quality?Mahattan Institute, April 27, 2017. Archived March 8, 2018.
  24. “Will EPA Cuts Harm America’s Air Quality?” (PDF), Manhattan Institute.
  25. The Problem With Climate Catastrophizing,” Foreign Affairs, March 21, 2017.
  26. Michael E. Mann. “Climate Catastrophe Is a Choice,” Foreign Affairs, April 21, 2017. Archived March 8, 2018. Archive.is URLhttps://archive.is/7aDHA
  27. Oren Cass. “Catastrophe and the Climate,” Foreign Affairs, May 21, 2017.
  28. Oren Cass. “Who Pays the Bill for the Obama Climate Agenda?” (PDF), the Manhattan Institute. Archived .pdf on file at DeSmogBlog.
  29. Oren Cass. “Who Pays the Bill for the Obama Climate Agenda?” (PDF), The Manhattan Institute. Archived .pdf on file at DeSmogBlog.
  30. “Four Energy and Environment Initiatives” (PDF), Manhattan Institute, December 2016.
  31. New American Leadership, Brexit and What’s Next,” Legatum Institute, November 17, 2016. Archived March 8, 2018. Archive.is URL: https://archive.is/3CTsA
  32. 2016 ANNUAL MEETINGINDIANAPOLIS, IN,ALEC.  Archived March 8, 2018. Archive.is URL: https://archive.is/r1x7q
  34. Testimony by Oren Cass to House Science Committee on Paris Climate Deal,” Manhattan Institute, Decembe 1,2 015. Archived March 9, 2018. Archive.is URLhttps://archive.is/uqiiS
  35. Testimony By Oren M. Cass to the Senate Environment and Public Works Committee,” Manhattan Institute, November 18, 2015. Archived March 9, 2018. Archive.is URL: https://archive.is/8JPJn
  36. Preparing for Paris: What to Expect from the U.N.’s 2015 Climate Change Conference,” Cato Institute, Octobe 30, 2015. Archived March 8, 2018. Archived .mp4 on file at DeSmog. Archive.is URL: https://archive.is/4cz8c
  37. Oren Cass. “Leading Nowhere: The Futility and Farce of Global Climate Negotiations” (PDF)Manhattan Institute.
  38. Scott Waldman. “Obama emissions plan has roots in New York debate,” Politico, August 4, 2015. Archived March 8, 2018. Archive.is URL: https://archive.is/92md7
  39. The President’s Hard Carbon Emissions Push,” WBUR 90.9, August 4, 2015. Archived .mp3 on file at DeSmog.
  40. Oren Cass responds to the encyclical written by Pope Francis that addressed climate change on Fox News,Manhattan Institute, June 18, 2015. Archived .mp4 on file at DeSmog.
  41. Oren Cass. “Changing Climate, Changing Claims,”Washington Examiner, May 14, 2015. Archived March 8, 2015. Archive.is URL: https://archive.is/ovS9y
  42. Overheated: How Flawed Analyses Overestimate the Costs of Climate Change,” Manhattan Institute, March 11, 2018. Archived March 12, 2018. Archive.is URL: https://archive.is/CG65Y
  43. Oren Cass. “Doomsday Climate Scenarios Are a Joke,” The Wall Street Journal, March 11, 2018. Archive.is URL: https://archive.is/LdeAF
  45. HAPPENING NOW: @oren_cass presents his new paper on climate research, ‘Overheated’” He was introduced by @BrianAcity,” Twitter post by user @ManhattanInst, March 20, 2018. Archived .png on file at Desmog
  46. Pruitt’s Plan for Climate Change Debates: Ask Conservative Think Tanks,” The New York Times, May 8, 2018. Archived May 14, 2018. Archive.is URL: https://archive.li/onsj5

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