Anonymous Retention of Newborn Blood Spots Not a Constitutional Violation: Sixth Circuit Defines Limits of Parental Due Process and Fourth-Amendment Rights

Introduction

In Adam Kanuszewski v. Michigan Department of Health & Human Services (6th Cir. 2025), a divided history of district-court rulings culminated in a sweeping reversal by the U.S. Court of Appeals for the Sixth Circuit. The decision resolves long-running constitutional challenges to Michigan’s newborn screening and bio-banking programme—challenges that strike at the heart of public-health policy nationwide.

Plaintiff parents and their minor children alleged that the State’s post-screening retention and research use of residual dried blood spots (DBS)—collected from virtually every newborn—violated (1) the parents’ substantive-due-process right to direct their children’s medical care under the Fourteenth Amendment and (2) the children’s Fourth-Amendment right to be free from unreasonable searches and seizures. After significant procedural detours (including Kanuszewski I, 927 F.3d 396 (6th Cir. 2019)), the district court ultimately sided with the plaintiffs and imposed an injunction compelling destruction or return of DBS and associated data.

The Sixth Circuit reversed in full, vacating the injunction and holding that (a) no fundamental parental right is implicated by the anonymised, non-diagnostic retention or research use of DBS, and (b) such retention/use is neither a “search” nor a “seizure” within the meaning of the Fourth Amendment where parents have no possessory interest and no cognisable privacy interest in anonymised specimens. The opinion creates an important precedent for public-health biorepositories and clarifies the boundaries between bodily-integrity rights and the State’s interests in population-level research.

Summary of the Judgment

• Fourteenth Amendment: The court held that storage and secondary uses of anonymised DBS do not interfere with the parents’ fundamental right to direct their children’s medical care. No “medical treatment” of the child occurs once screening is complete, and the post-screening uses are too remote from bodily integrity to be treated as a protected liberty interest.
• Fourth Amendment – Searches: Quality-assurance, equipment-calibration, and third-party research performed on anonymised DBS are not searches because they do not seek personal information about the individual donor; the mere transfer to researchers likewise does not implicate privacy.
• Fourth Amendment – Seizures: Plaintiffs failed to prove any possessory interest in the DBS or in the State’s derivative data, a prerequisite to establishing a seizure. Therefore continued retention is not a seizure.
• Relief and Injunction: Because no constitutional violation remained, the Sixth Circuit reversed summary judgment, reversed the bench-trial judgment, and vacated the district court’s injunction directing destruction of data.
• Secondary Holdings: The Court rejected arguments based on mootness and law-of-the-case, emphasising that merits review was necessary despite interim destruction of physical DBS.

Analysis

Precedents Cited and Their Influence

The panel—Judges Griffin (author), Nalbandian, and Mathis—relied extensively on Supreme Court and Sixth Circuit precedent to cabin the constitutional claims.

• Washington v. Glucksberg, 521 U.S. 702 (1997) & Cruzan, 497 U.S. 261 (1990): provide the template for recognising fundamental rights; the court stresses Glucksberg’s “careful description” test and refutes any expansion to cover DBS storage.
• Troxel v. Granville, 530 U.S. 57 (2000): establishes the venerable parental-rights doctrine, but the court distinguishes Troxel because DBS storage does not commandeer parental decision-making about medical care.
• Skinner v. Railway Labor Executives’ Ass’n, 489 U.S. 602 (1989) & Chandler v. Miller, 520 U.S. 305 (1997): confirm that chemical testing of bodily fluids is a search; yet, the panel limits Skinner to contexts where information about the individual is revealed.
• Jacobson v. Massachusetts, 197 U.S. 11 (1905): classic vaccination precedent; used to illustrate when State-imposed medical procedures intrude on bodily integrity.
• United States v. Jones, 565 U.S. 400 (2012) & Katz v. United States, 389 U.S. 347 (1967): supply the dual property- and privacy-based frameworks for searches; the court finds neither satisfied.
• Albrecht v. Treon, 617 F.3d 890 (6th Cir. 2010): utilised for the rule that state law defines possessory interests; plaintiffs’ failure to demonstrate such an interest is fatal to seizure claims.
• United States v. Karo, 468 U.S. 705 (1984): reinforces that speculation about future use (e.g., crime-victim identification) is not ripe for constitutional adjudication.
• Capen v. Saginaw County, 103 F.4th 457 (6th Cir. 2024): recent Sixth Circuit authority distinguishing between medical evaluation (information-gathering) and compulsory treatment; heavily relied upon to analogise DBS storage to merely descriptive conduct.

Legal Reasoning Explained

1. Limiting the Right to Direct a Child’s Medical Care.
   The court meticulously separated the newborn heel-prick (already excluded from the appeal) from subsequent State actions. Post-screening storage, anonymisation, and research neither manipulate the child’s body nor impose treatment. Relying on Capen, the court found the conduct “descriptive” rather than “therapeutic”. Because no fundamental right was burdened, rational-basis review would normally apply; but the panel ended analysis after finding no right at stake, making reasonableness scrutiny unnecessary.
2. No Search Absent Information About the Individual.
   Under Katz, a search requires infringement of a reasonable expectation of privacy. Anonymised DBS stripped of identifiers does not reveal personal data. Even State solicitation of outside researchers does not transform the activity into a government search, as researchers receive only non-identifiable specimens. The court stresses precedent in privacy-statute cases (In re Nickelodeon, Zynga, Harper v. Werfel) to show that anonymised “static identifiers” do not attract constitutional privacy.
3. No Seizure Without a Property Interest.
   A seizure requires “meaningful interference” with the plaintiff’s possessory interest. The panel noted Michigan’s statutory scheme (Mich. Comp. Laws § 333.5431) vests discretion in MDHHS to retain or dispose of DBS, suggesting no private ownership. Plaintiffs produced no contrary authority; thus, they could not satisfy the first element of a seizure claim. The court therefore declined to decide the state-law property question, resolving the federal claim solely on plaintiffs’ evidentiary failure.
4. Procedural Bars Rejected.
   • Mootness: Although the physical DBS were returned or destroyed during appeal, a live controversy remained over the constitutionality of the programme and the data.
   • Law-of-the-Case: The panel clarified that its earlier, plausibility-stage decision (Kanuszewski I) did not dictate the ultimate merits because the record was undeveloped at that time, citing McKenzie v. BellSouth, 219 F.3d 508 (6th Cir. 2000).

Impact of the Judgment

• Public-Health Programs Nationwide: Every state operates newborn screening programmes with residual DBS repositories. The ruling provides a robust defence against constitutional challenges predicated on due-process bodily-integrity or Fourth-Amendment theories, so long as specimens are anonymised and post-screening use is unrelated to the donor’s treatment.
• Biorepository Governance: The opinion implicitly favours statutory and regulatory frameworks that strip identifiers and allow opt-out mechanisms, signalling that anonymisation + minimal parental control passes constitutional muster.
• Privacy Litigation Trend: Raises the bar for plaintiffs seeking to frame data-privacy grievances as bodily-integrity or search-and-seizure cases. Litigants must show personally identifiable information exposure or property-like interests.
• Qualified-Immunity Landscape: Because the Sixth Circuit found no constitutional violation, future state actors involved in neonatal biobanking may more easily invoke qualified immunity; but the court also signalled that warrantless non-anonymised forensic use could still raise Fourth-Amendment issues.
• Legislative Incentives: Legislatures may codify parental notification and restricted research categories to further insulate programmes, while still enabling valuable population-health research.

Complex Concepts Simplified

• Substantive Due Process: A doctrine that protects certain fundamental rights from government interference, even when the government provides procedural safeguards. To qualify, a right must be “deeply rooted” in U.S. history and tradition.
• Bodily Integrity vs. Medical Care: Bodily-integrity rights shield individuals from unwanted physical intrusions (e.g., forced medication). Once a blood sample is taken lawfully, later storage of the sample—without further bodily contact—does not intrude on bodily integrity.
• Search vs. Seizure: A “search” implicates privacy—looking for information; a “seizure” implicates property—taking control. Anonymised DBS used for general research is neither.
• Possessory Interest: The legal right to control or own property. If state law does not grant parents ownership of DBS, retention by the State is not a seizure.
• Law-of-the-Case Doctrine: Prevents relitigation of issues already decided in earlier phases of the same case but allows reconsideration when factual records change, as here between motion-to-dismiss and summary-judgment/trial stages.
• Mootness: A case becomes moot when courts can no longer grant effective relief. Even after DBS destruction, the State still faced injunctive orders regarding data, keeping the controversy alive.

Conclusion

The Sixth Circuit’s 2025 decision in Kanuszewski delineates a crucial constitutional boundary: the State’s retention and anonymous use of newborn dried blood spots for research or public-health purposes does not infringe parental substantive-due-process rights nor violate the Fourth Amendment, absent disclosure of personally identifiable information or proof of a property interest. By disentangling bodily-integrity claims from data-privacy concerns and by emphasising the search/seizure distinction, the court provides a coherent framework for adjudicating similar biobanking disputes nationwide. The ruling underscores that constitutional protections, while robust, are not absolute shields against every perceived encroachment—especially when the State pursues demonstrably lifesaving public-health initiatives through anonymised data. Future litigants must therefore craft more precise theories and evidentiary showings to prevail against well-structured public-health repositories.