03/05/2021 - Federal Policy Analysis

The Downfall of the “Secret Science” Rule, and What It Means for Biden’s Environmental Agenda

by Hannah Perls

Under President Trump, EPA intended to limit which scientific studies it will consider, which would have undermined settled conclusions about the health impacts of air pollution. This is Part 4 of 4. Part 1 explains the origins of this effort and why it matters, Part 2 outlines the shortcomings in EPA’s proposed rule, and Part 3 discusses comments by health experts on the proposed rule.

The Trump EPA’s infamous “Secret Science” rule sought to permanently constrain the agency’s ability to rely on the best available public health data to set pollution standards. Specifically, the final rule required EPA to assign less weight to scientific studies if the data underlying those studies weren’t publicly available. When a federal court vacated the rule on January 27, it removed a major roadblock in the Biden administration’s pursuit of setting aggressive health-based standards for environmental pollution. The administration must now consider its options for protecting apolitical science-based decision-making processes from future deregulatory administrations.

The Rule’s Substantive Effect

From the beginning, the Trump EPA’s Strengthening Transparency in Regulatory Science rule, also known as the Secret Science Rule, met stiff opposition. Both the proposed rule and the supplemental notice of proposed rulemaking showed significant legal weaknesses.[1] EPA finalized the Secret Science Rule on January 6, 2021, claiming the final rule was “much narrower” in scope than the proposed rule. However, the final rule broadly applied its standards to the agency’s use of “dose-response data”[2] in both “significant regulatory actions” and the general sharing of “influential scientific information,” such as information shared on EPA’s website.

The final rule stated that “for pivotal science where there is no access to dose-response data, or access is limited, the Agency may still consider these studies but will give them lesser consideration.”[3] The rule thus created a new default in which key epidemiological studies were assumed to be excluded from EPA review unless the agency affirmatively opted to include those studies in its decision and rule-making processes. Even then, EPA was required to give those studies “lesser consideration” simply because the underlying data are not publicly available. The final rule also invited EPA to conduct additional internal peer review of “pivotal” science, even if those studies had already undergone independent peer review.[4]

Public health experts expressed special concern with the rule’s effect on two studies—the Harvard Six Cities Study and the American Cancer Society’s Cancer Prevention Study II—that form the bedrock of particulate matter (PM) pollution regulations. In these studies, the researchers tracked personal medical, occupational, and home location data for tens of thousands of participants for nearly two decades, on the condition that the participants’ personal information would remain confidential. Administrator Wheeler stated that under the final rule, “pivotal studies” like the Six Cities Study “will [not] automatically be cut from review by the agency,” provided that EPA can justify the study’s use and publish its reasoning behind that decision. Thus, the rule imposed new procedural burdens discouraging EPA from relying on these studies. And if EPA did choose to use these studies, the agency would have to give those studies less weight simply because the study uses anonymized data from human subjects.[5] The rule does allow the EPA Administrator to seek an exemption to use a particular study on a case-by-case basis. To do that, however, the administrator must document their rationale for the exemption, which may then be subject to legal challenges.[6] Thus the rule disincentivized EPA from relying on these critical studies by increasing the agency’s administrative burden and legal exposure.

The Rule’s Downfall

In issuing the final rule, EPA relied on the little-known Federal Housekeeping Statute. The statute gives certain agencies the authority to issue procedural rules “for the government of [the] department, the conduct of its employees, the distribution and performance of its business, and the custody, use, and preservation of its records, papers, and property,”[7] which the Supreme Court later interpreted as giving agencies the authority “to govern internal departmental affairs.”[8] While EPA does not appear on the Federal Housekeeping Statute’s list of agencies, the Trump EPA argued that its founding statute gave it equivalent authority.[9]

Like many rules issued in the final days of the Trump administration, EPA also claimed “good cause” to make the rule effective immediately. Under the Administrative Procedure Act (APA), an agency must show “good cause” (or satisfy one of two other exceptions under the law) to make the law effective less than 30 days from its publication date. EPA first claimed that, because the Secret Science rule is purely procedural, it is exempt from the APA’s 30-day notice requirement. Alternatively, EPA claimed that the rule’s “immediate implementation . . . is crucial for ensuring confidence in EPA decision-making.”

After the Rule was published on January 6, environmental groups promptly filed suit in the U.S. District Court for the District of Montana, followed by two motions for partial summary judgment. In the first motion, plaintiffs argued that EPA improperly invoked the Federal Housekeeping Statute to issue a substantive rule. Alternatively, in the second motion, plaintiffs argued that EPA improperly claimed “good cause” to make the final rule effective immediately, seeking to delay the rule’s effective date by 30 days. Both arguments rested on the argument that, despite EPA’s claims to the contrary, the Secret Science rule is substantive in nature.

On January 27, 2021, Chief Judge Brian Morris granted plaintiffs’ second motion, finding the Secret Science rule “is no mere internal house-keeping measure,” but rather “makes a substantive determination as to how the agency should weigh scientific information in future rulemakings.” The court stated that the “critical factor” in deciding whether a rule is procedural or substantive is the extent to which it constrains the agency’s discretion and that the Secret Science rule “narrowly limits the agency’s discretion to consider certain scientific research when conducting future rulemakings.” Because the rule is substantive, the rule was therefore not exempt from APA’s notice requirements; the court also found EPA’s alternative “good cause” justification was insufficient. After the court delayed the rule’s effective date, the Biden administration quickly asked the court to vacate the entire rule based on the finding that the rule is substantive, and thus could not be issued under the Federal Housekeeping Statute. On February 1, the court granted the motion, vacating and remanding the rule to EPA.

Next Steps for the Biden Administration

Before the Secret Science rule was struck down, Congressional Democrats were reportedly considering using the Congressional Review Act to undo the rule. On inauguration day, President Biden’s Executive Order 13990 on Public Health and the Environment explicitly instructed EPA to consider revising or rescinding the Secret Science Rule “as soon as possible,” one of the few rules to be reviewed on such a short timeframe. The rule would have severely constrained the Biden administration in addressing Trump-era regulatory rollbacks and setting new health-based pollution standards, including revisiting ambient air quality standards for soot and ozone, and increasing limits on power plants’ emissions of hazardous air pollutants. Now that the rule has been struck down, EPA will be able to prioritize reversing other Trump-era environmental rollbacks that continue to constrain EPA.

In his first week in office, President Biden also made affirmative commitments to make evidence-based decisions guided by the best available science and data. On January 27, Biden issued Executive Order 14007 directed at the President’s Council on Advisors on Science and Technology (PCAST), as well as a memo on “Restoring Trust in Government Through Scientific Integrity and Evidence-Based Policymaking.” The memo explicitly states that “scientific findings should never be distorted or influenced by political decisions,” and scientific or technological information should be “subjected to well-established scientific processes . . . with appropriate protections for privacy.” As a first step to enforcing these policies, Biden entrusts the OSTP Director with various responsibilities, including ensuring each agency establishes and enforces “scientific-integrity” policies, and convening an interagency Task Force on Scientific Integrity. The OSTP Director’s review must be completed within 120 days, and the findings will be published on the OSTP website, including recommended best practices and lessons learned. The memo then provides a framework for each agency to submit updated policies to the OSTP Director, who will “expeditiously review” those policies to ensure they respond to the Task Force’s analysis.

Now that the Secret Science rule has been sent back to EPA, the agency will likely be guided by these policy priorities in determining whether to develop new guidance or internal policy, or whether to pursue notice and comment rulemaking to further enshrine the administration’s priorities. Should the agency choose to issue a new rule that significantly constrains the agency’s discretion in future rulemaking, and is therefore substantive, it will need to find a new statutory authority under which to issue that rule.


[1] EPA issued a supplemental notice of proposed rulemaking in March 2020 to address the numerous issues raised in public comments on the proposed rule. Yet instead of addressing the public’s concerns, the supplemental rule broadened the scope of the proposed rule to all “influential science” relied on by EPA, not just science used in regulatory efforts. Furthermore, under the supplemental rule, the EPA administrator would have complete discretion to decide which studies are subject to the rule. Kelsey Brugger, Trump admin expands reach of secret science proposal, E&ENews (Mar. 4, 2020), https://www.eenews.net/stories/1062516587/.

[2] Dose-response studies evaluate how much a person’s exposure to a potentially harmful substance increases the risk of harm.

[3] “Strengthening Transparency in Pivotal Science Underlying Significant Regulatory Actions and Influential Scientific Information,” 86 Fed. Reg. 469, 492 (Jan. 6, 2021) (emphasis added). The rule exempts pivotal science based on dose-response data that includes confidential business information, proprietary information, or personally identifiable information if those data are made available to EPA through restrict access “in a manner sufficient for independent validation.” Id.

[4] Id. at 487. The final rule’s peer review requirements are narrower than in the proposed rule, which would have required EPA to conduct independent peer review of all “pivotal regulatory science” used in rulemaking decisions.

[5] Id. at 477.

[6] Id. at 493.

[7] 5 U.S.C. § 301.

[8] Chrysler Corp. v. Brown, 441 U.S. 281, 309 (1979).

[9] 86 Fed. Reg. at 471.