We’re not bashful about our affinity for real science. It underpins our clients’ ability to develop life-saving drugs and devices, supports Rule 702’s role in keeping junk science out of courtrooms, and reflects the skeptical habits of mind that should matter to everyone. Shortly before his death in 1996, Carl Sagan discussed with Charlie Rose the dangers of a society where fundamental understandings of science and technology continue to diminish:

There [are] two kinds of dangers. One is . . . [t]hat we’ve arranged a society based on science and technology in which nobody understands anything about science and technology, and this combustible mixture of ignorance and power, sooner or later, is going to blow up in our faces. I mean, who is running the science and technology in a democracy if the people don’t know anything about it? And the second reason that I’m worried about this is that science is more than a body of knowledge. It’s a way of thinking. A way of skeptically interrogating the universe with a fine understanding of human fallibility. If we are not able to ask skeptical questions, to interrogate those who tell us that something is true, to be skeptical of those in authority, then we’re up for grabs for the next charlatan political or religious who comes ambling along. It’s a thing that Jefferson laid great stress on. It wasn’t enough, he said, to enshrine some rights in a Constitution or a Bill of Rights. The people had to be educated, and they had to practice their skepticism and their education.

Carl Sagan’s Last Interview. Fast forward, and today we’re discussing a case where the court quotes Carl Sagan and notes that, in the context of vaccines, science is “the best we have.”  Am. Acad. of Pediatrics v. Kennedy, __ F. Supp. 3d __, 2026 WL 733828 (D. Mass. Mar. 16, 2026).  Through a combination of good science and government oversight, the United States’ vaccination program has been a beacon for public health: 

Congress and the Executive have built—over decades—an apparatus that marries the rigors of science with the execution and force of the United States government. One extraordinary product of that apparatus has been the eradication and reduction of certain communicable diseases through the development and use of vaccines.  In the words of the Centers for Disease Control and Prevention (CDC), vaccines are one of the greatest achievements of biomedical science and public health.

Id. at *1 (cleaned up).  That success in the eradication of certain diseases is based on a rigorous method by which decisions about vaccine policy are made—“a method scientific in nature and codified into law through procedural requirements.” Id.  In this case, that rigorous and well-established method (both scientific and legal) was ignored.

We’ve previously posted on our concerns about ideology overriding legitimate science, and we’ve been disheartened to see arbitrary and capricious decisions become a management style. Here, the court addressed arbitrary and capricious agency actions involving: (1) the termination in June, 2025, of all 17 members of the Advisory Committee on Immunization Practices (“ACIP”), which since 1964 has provided expert guidance on the clinical use of vaccines; and (2) substantial changes issued in January 2026 to the CDC’s childhood immunization schedule (including reducing the number of childhood vaccinations considered “routine” from 17 to 11, limiting the recommendations for certain vaccines to high risk groups only, and downgrading designations for other vaccines from routine to “shared clinical decision making”). Id. at *5.  

Plaintiffs sought a preliminary injunction against the Department of Health and Human Services (“HHS”), the Secretary of HHS, Robert Kennedy, Jr., the CDC, and the acting director of the CDC.  Plaintiffs alleged that the defendants’ actions violated the Administrative Procedure Act (“APA”) because they were arbitrary and capricious and contrary to law.  The defendants argued that their actions were not reviewable because they were (1) not final agency actions, and (2) committed to agency discretion.  Step one of the court’s analysis was thus to determine whether the agency actions were “final” and reviewable under the APA.

The court determined the defendants’ actions were final. The actions reflected the consummation of the decision-making process of HHS and CDC, and they were actions from which “legal consequences will flow.” Id. at *6.  When the American Academy of Pediatrics disagreed with the CDC’s updated immunization schedule and published its own recommended list of childhood vaccines, Secretary Kennedy commented on social media:

[The American Academy of Pediatrics (“AAP”)] today released its own list of corporate-friendly vaccine recommendations. . . . AAP should also be candid with doctors and hospitals that recommendations that diverge from the CDC’s official list are not shielded from liability under the 1986 Vaccine Injury Act.

Id. at *4.  Given Secretary Kennedy’s statement about potential liability, the court found it clear that “changing legal liability for vaccine administration is agency action from which legal consequences will flow.”  Id. at *6.

Turning next to whether the agency actions violated the APA, the court looked to the required ACIP involvement in the issuance of immunization schedules. It was undisputed that the CDC revised the immunization schedule without consulting the ACIP, so if such consultation was required the CDC’s action was contrary to law. ACIP consultation was required. The court found it clear that, for decades and based on the CDC’s own processes, the CDC’s immunization schedules were to be based on input from the ACIP, and Congress required the ACIP’s specific involvement. The CDC ignored that step here, so the court held the new immunizations schedules were issued contrary to law. Id. at *9.

The court also held that the changes to the immunization schedules were arbitrary and capricious.  The APA’s arbitrary and capricious standard requires agency actions to be “reasonable and reasonably explained.” Id. at *11.  But the CDC’s changes to the immunization schedule “abandoned the agency’s longstanding practice of getting recommendations from the ACIP before changing the immunization schedules.”  Id.  And the record lacked any explanation for bypassing the ACIP.

The defendants asserted that the issuance of the updated schedule was “committed to agency discretion,” and therefore not subject to judicial review. The court found that argument could “only be countenanced if one completely abandons the idea of objective fact, a nihilist endeavor this Court does not find appropriately read into Congress’s public health statutes.” Id. at *9. At oral argument, the court asked defense counsel: “So even if what the agency was saying is ‘we like communicable diseases and we think you should get more of them,’ that’s not judicially reviewable?” Id. at *10. Defense counsel responded that it would still not be reviewable.  That response underscored the court’s view that the defendant’s position could not be squared with Congressional intent regarding “the prevention and suppression of communicable diseases.” Id. (quoting 42 U.S.C. § 243(a)).    

Turning to the wholesale reconstitution of the ACIP, plaintiffs claimed that the new members lacked the qualifications and expertise necessary to achieve ACIP’s function—which is to “develop recommendations on the use of vaccines in the civilian population of the United States.”  Id. at *14.  While the court noted it typically defers to an agency’s decisions in forming committees, it held the plaintiffs were likely to succeed on the merits of their claim about the ACIP.  Federal regulations require that advisory committees should include individuals “with demonstrated professional or personal qualifications and expertise relevant to the functions and tasks to be performed by the committee.”  Id. at *15 (quoting 41 C.F.R. § 102-3.60(b)(1)) (emphasis in original).   Beyond that, the ACIP’s charter documents provide that committee members should be “knowledgeable in the fields of immunization practices and public health, have expertise in the use of vaccines . . ., or have expertise in assessment of vaccine safety or efficacy.” Id. 

The court found “glaring gaps” between these requirements and the new ACIP members’ qualifications. Of the fifteen members on the new ACIP, only six “even under the most generous reading” had any meaningful experience in vaccines. Id. And at least six of the members appeared to lack “any expertise or professional qualifications related to vaccines or immunization as required by ACIP’s Charter.” Id. (emphasis in original). The ACIP is a committee “specifically dedicated to the use of vaccines and related agents for the effective control of vaccine-preventable diseases,” but as to that function the new committee members were “distinctly unqualified.” Id.

The court also found fault with the procedure the agency followed for replacing all of the ACIP members.  The ACIP has a membership balance plan that requires a broad email solicitation for potential members, submission of credentials and reference letters, ethics and conflicts checks, followed by an in-depth review of applicants by the ACIP steering committee. That process typically takes about two years. But here, “the most generous description of the appointment process is that it took a few months and involved some limited outreach to candidates.” Id. at *16. Given all this, the court held that the plaintiffs were likely to prevail on the merits of their claim that the agency’s actions were arbitrary and capricious.  Id. at *17. 

The court also found the plaintiffs were subject to irreparable harm because of (1) financial harm due to uncompensated work performed by doctors related to the new immunization schedule, and (2) financial harm related to uncompensated work by the organizational plaintiffs in supporting their members in complying with the challenged agency actions.  Those costs were substantial, and there was no dispute that the plaintiffs would have no avenue to recover those costs even if the agency’s actions were ultimately deemed unlawful. As a result injunctive relief was appropriate.

In fashioning its relief, the court stayed the January 2026 changes to the CDC’s childhood vaccination schedule and stayed both the appointment of the new members of the ACIP and all votes taken by the newly reconstituted ACIP. Id. at *21-22. Agencies are not entitled to pretend that regulatory procedure, expert-advisory structure, and their own governing documents are optional.  The court’s relief returns the CDC’s vaccine schedule to the prior version and presumably leaves the CDC to try again to assemble members for the ACIP.  Although this saga will continue, for now the court’s decision reinforces the fact that agencies cannot substitute ideology for the legitimate process that Congress and the regulations require.