After fielding just a few questions on climate change early in her confirmation hearing, U.S. Supreme Court nominee Amy Coney Barrett appeared to signal skepticism about whether a scientific consensus exists that human activities are significantly contributing to global warming.

Barrett made the comments on the third day of hearings on her nomination before the U.S. Senate Judiciary Committee. Although the hearings have focused largely on healthcare, abortion and other policy issues, Democrats pushed Barrett to share her views on climate science, with the Supreme Court the key decider on legal challenges to federal rules to regulate greenhouse gas emissions.

"I'm going to ask you about an issue that really hasn't been raised much here: climate change," said U.S. Sen. Richard Blumenthal. The Connecticut Democrat noted that Sen. John Kennedy, R-La., asked Barrett for her views on the issue the day before, to which she replied that she is "not a scientist" and does not hold "firm views" on it.

"Do you believe that human beings cause global warming?" Blumenthal asked again.

"I don't think I am competent to opine on what causes global warming or not," Barrett replied.

Blumenthal then pressed Barrett on whether she agrees with President Donald Trump's stance on climate change. Trump called the problem "a hoax" perpetrated by China during his 2016 presidential campaign and his administration has sought to reverse his predecessor's signature climate policies through deregulation while pulling the U.S. out of the Paris Agreement on climate change.

"I don't know that I have seen the president's expression of his views on climate change," Barrett said.

Sen. Kamala Harris, D-Calif., Joe Biden's running mate in the 2020 elections, revisited the issue with Barrett during later questioning.

"I certainly do believe your views are relevant and I'm very concerned about your statements," Harris said. The vice presidential nominee noted the scientific consensus that human activities are significantly contributing to rising global temperatures has only grown stronger since the Supreme Court issued a landmark decision in 2007 — Massachusetts v. EPA — affirming the U.S. Environmental Protection Agency's authority to regulate carbon dioxide as a harmful air pollutant.

"If a case comes before me involving environmental regulation, I will certainly apply all applicable law deferring when the law requires me to, and as I'm sure you know Senator Harris, the Administrative Procedure Act does require courts to defer to agency fact-finding, and to agency regulations when they're supported by substantial evidence," Barrett said.

Pressing harder, however, Harris asked Barrett whether she believed COVID-19 and smoking are harmful to human health. After Barrett answered yes on both counts, Harris asked, "Do you believe that climate change is happening and it's threatening the air we breathe and the water we drink?"
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In response, Barrett told Harris, "You have asked me a series of questions that are completely uncontroversial like whether COVID-19 is infectious, whether smoking causes cancer, and then trying to analogize that to elicit an opinion on a very contentious matter of public debate."

"Judge Barrett, you've made your point clear that you believe it's a debatable point," Harris replied.

Judicial philosophies

Over several days of hearings, Barrett discussed her broader judicial philosophies. She affirmed her adherence to originalism, an approach that legal experts say could give federal agencies less leeway on climate and environmental policies if Barrett is confirmed. The Supreme Court would have an expanded, 6-3 conservative majority if the GOP-majority Senate backs her nomination, as is likely.

Under originalism, Barrett said judges interpret the U.S. Constitution's provisions based on their "original public meaning" when they were adopted. She also embraces textualism, which applies the same principles to congressional statutes.

"I, as a judge, have an obligation to respect and enforce only that law that the people themselves have embraced," Barrett said. "And I think originalism and textualism to me boil down to… a commitment to the rule of law, to not disturbing or changing or updating or adjusting in line with my own policy preferences what that law requires."

With Barrett nominated to replace progressive Justice Ruth Bader Ginsburg, who died on Sept. 18, Democratic committee members worry her confirmation could limit federal agencies' ability to implement regulations, including with respect to environmental protections.

"My core concern here … is that your confirmation may launch a new chapter of judicial conservative activism unlike anything we've seen in decades," U.S. Sen. Chris Coons, D-Del., said.

Barrett said she backed the legal doctrine of stare decisis, which obligates courts to follow precedent from past cases when deciding on similar litigation. That doctrine particularly applies to "super-precedents," such as the Brown v. Board of Education ruling ending public school segregation. Those precedents are so well established that overruling them would be "unthinkable" and could not happen without state or congressional legislatures enacting new policies, Barrett said.

But Coons pointed to Barrett's comments in a law review article stating that courts should overrule precedent if a litigant shows that a prior decision clearly misinterpreted the relevant statute or Constitutional provision. That view "basically means any precedent is at risk where your originalist view of the Constitution or textualist view of the statue says it's clearly wrong," he said.

Barrett, who currently sits on the U.S. Court of Appeals for the 7th Circuit, said her comments pertained to appeals court rules that do not apply at the Supreme Court. "I don’t think there is any evidence that I’ve been unwilling to follow or apply circuit precedent," she maintained.

Sen. Mike Crapo, R-Idaho, cited writings by Barrett calling stare decisis a "fixture" of the judiciary and saying that courts should not depart from precedent unless that decision is erroneous and unworkable. "I found it amazing that you would be accused of being a judicial activist," Crapo said.

One legal expert said the term super-precedent is not well defined but is unlikely to extend to rulings in cases such as Massachusetts v. EPA. Nathan Richardson, an associate professor at the University of South Carolina School of Law, said the 2007 court decision has already been "substantially eroded" by other Supreme Court rulings on climate litigation. Those rulings include the high court's stay of the Obama administration's Clean Power Plan and its 2014 decision in UARG v. EPA, which found the agency could not require permits for greenhouse gas emissions for thousands of smaller stationary sources.

"In spite of this erosion, or perhaps because of it, I don't think it's likely Massachusetts v. EPA gets overturned," Richardson said. "There's just not much need to do it."

The "far greater threat to climate policy," according to Richardson, is "possible changes to broader administrative law doctrines that constrain the ability of Congress to delegate authority to agencies."

Barrett's appointment comes as multiple high-profile climate-related lawsuits work their way toward the Supreme Court, noted Jennifer Rushlow, director of the environmental law center at Vermont Law School.

"Environmental law is a relatively new field," Rushlow said in an email. "The super-precedent of environmental law — and particularly energy and climate law — is actively under development now."