Warrant Required for Forensic DNA Testing of an Arrestee’s Effects Held in Jail Custody When Sought for an Unrelated Crime

Introduction

People of Michigan v. David Henry Serges (Mich Sup Ct, July 30, 2026) addresses whether police may, without a warrant or consent, submit an incarcerated person’s clothing—already held in jail custody—to forensic DNA testing in order to investigate a different offense than the one for which the person was arrested and detained.

The defendant, David H. Serges, was convicted of first-degree murder, MCL 750.316, after a second trial (the first ended in a hung jury). The State’s key physical evidence was a lab result showing a tiny bloodstain on his pants matched the victim’s DNA. The pivotal procedural posture was an ineffective-assistance claim: trial counsel never moved to suppress the DNA results, and the defense later argued the testing itself was an unconstitutional search under Const 1963, art 1, § 11.

The central issues were: (1) whether the DNA testing was a “search”; (2) if so, whether it was “reasonable” under any warrant exception—especially inventory search or search incident to arrest; and (3) whether counsel’s omission to litigate suppression was constitutionally ineffective and prejudicial.

Summary of the Opinion

The majority (Justice BERNSTEIN, joined by Chief Justice CAVANAGH and Justices WELCH, BOLDEN, and THOMAS) held:

  • Submitting defendant’s pants for DNA testing without a warrant or consent was a search and an unreasonable search under Const 1963, art 1, § 11.
  • The testing was not justified by the inventory-search exception because DNA testing is not part of standardized inventory procedures and served investigative, not administrative/safety, purposes.
  • The testing was not justified by the search-incident-to-arrest exception, particularly because, under People v Carr, 370 Mich 251 (1963), and People v Trudeau, 385 Mich 276 (1971), Michigan’s Constitution does not allow warrantless “incident” searches for evidence of another crime when the person is arrested/incarcerated for a different one.
  • Trial counsel was ineffective under Strickland v Washington, 466 US 668 (1984) for failing to move to suppress; the error was prejudicial because the DNA evidence was the only physical evidence linking defendant to the murder.

The Court reversed the Court of Appeals and remanded for further proceedings.

Justice ZAHRA dissented, arguing no “search” occurred because defendant had no reasonable expectation of privacy in pants lawfully in jail custody pursuant to inventory procedures, and contending the majority misapplied the “trespass” theory to property already lawfully possessed by police.

Analysis

Precedents Cited

1) Defining “Search”: Trespass Approach vs. Privacy Expectation

The majority anchored its “search” determination in the trespass-based line of authority:

  • United States v Jones, 565 US 400 (2012): A search occurs when the government “occupie[s] private property for the purpose of obtaining information.” The majority applied this formulation directly to forensic DNA analysis of the defendant’s “effects.”
  • Johnson v VanderKooi, 509 Mich 524 (2022): Reaffirmed the viability of the trespass approach in Michigan and articulated the two-part inquiry (physical trespass on a constitutionally protected area plus attempt to obtain information). This case supplied the doctrinal tool the majority used to avoid resolving the dispute on “reasonable expectation of privacy” grounds.
  • Florida v Jardines, 569 US 1 (2013): Quoted (via Johnson v VanderKooi) for the proposition that a property-rights baseline “keeps easy cases easy,” supporting the majority’s view that once trespass-based “search” is found, the Katz inquiry is unnecessary.
  • Katz v United States, 389 US 347 (1967) and Kyllo v United States, 533 US 27 (2001): Recognized the alternative “reasonable expectation of privacy” framework. The majority emphasized this approach exists “independently of and alongside” trespass, but did not apply it because trespass sufficed.
  • People v LoCicero (After Remand), 453 Mich 496 (1996): Cited for the principle that a search cannot be justified retroactively by what it reveals (“A search is not to be made legal by what it turns up.”), rebutting the prosecution’s attempt to treat “someone else’s DNA on the exterior” as outside constitutional protection.

The dissent’s counterweight relied on the Katz line (and diminished privacy in custody) rather than trespass. It argued the majority’s trespass move collapses because “trespass” is incoherent where police already lawfully possess the item.

2) Warrant Exceptions: Inventory Searches

The majority treated inventory searches as an administrative step and rejected the claim that forensic testing is part of inventory:

  • Illinois v Lafayette, 462 US 640 (1983): The core inventory-search authority the majority used to describe inventory’s justifications (property protection, claims prevention, safety). The Court reasoned DNA testing serves none of those purposes and is not a standardized inventory practice.
  • South Dakota v Opperman, 428 US 364 (1976): Cited for inventory’s three classic justifications (owner’s property, police protection from claims, police safety). The majority measured DNA testing against these purposes and found a mismatch.
  • People v Toohey, 438 Mich 265 (1991): Used to reinforce inventory searches’ administrative (not investigative) nature in Michigan jurisprudence.

The majority contrasted inventory’s limited rationale with what happened here: Detective Freeman removed the pants from the jail property room into police evidence and, weeks later, had them tested specifically to investigate homicide.

3) Warrant Exceptions: Search Incident to Arrest, and the “Same-Offense” Limitation Under Michigan Law

The majority accepted the general existence of the exception but held Michigan’s Constitution, as construed by Michigan precedent, bars its use to search for evidence of a different crime than the one underlying detention:

  • United States v Edwards, 415 US 800 (1974) and Cooper v California, 386 US 58 (1967): The prosecution’s principal authorities. The majority distinguished them because those searches were “closely related” to the reason for arrest/impoundment—i.e., evidence of the offense of arrest.
  • Arizona v Gant, 556 US 332 (2009): Cited for limiting the evidentiary rationale of search incident to arrest to “evidence of the offense of arrest.”
  • Preston v United States, 376 US 364 (1964): Used to underline that a search remote in time/place from arrest is harder to characterize as “incident” to arrest—particularly relevant because the testing occurred more than a month after custody began.
  • People v Carr, 370 Mich 251 (1963): The decisive Michigan authority. Carr held that incarceration for one offense does not permit a warrantless search for evidence of another, warning against “circumvent[ing] the constitutional guaranty” by stripping jailed misdemeanor defendants of civil liberties. The majority treated Carr as a direct constitutional constraint under Michigan’s search-and-seizure provision.
  • People v Trudeau, 385 Mich 276 (1971): Reinforced Carr. Trudeau rejected warrantless seizure/testing of clothing (a shoe) for an unrelated crime while the defendant was in custody on another charge, stating that absent custody police would have needed a warrant.
  • People v Gonzales, 356 Mich 247 (1959) and Virginia v Moore, 553 US 164 (2008): Cited as general search-incident-to-arrest authorities recognizing the exception, but not expanding it beyond its justifications.

A key factual predicate was the trial court’s finding that defendant was arrested and detained on the unrelated misdemeanor. The majority held the Court of Appeals erred by displacing that finding, invoking deference principles to trial-court factfinding.

4) State Constitutional Independence

The majority framed its holding explicitly under Michigan’s Constitution and emphasized that Michigan can diverge from federal Fourth Amendment doctrine:

  • People v Goldston, 470 Mich 523 (2004): Michigan is not bound by federal interpretation even where language is identical.
  • People v Nash, 418 Mich 196 (1983) and Sitz v Dep’t of State Police, 443 Mich 744 (1993): Used to explain that the “compelling reason” language does not create a conclusive presumption tethering Michigan to federal law and that Michigan must independently analyze its Constitution.
  • People v Tanner, 496 Mich 199 (2014) and People v Slaughter, 489 Mich 302 (2011): Cited to support independent state-constitutional analysis and that Michigan provides at least as much protection as the Fourth Amendment.

The dissent, in contrast, leaned on the coextensive-history line and cited decisions like People v Mead, 503 Mich 205 (2019) and others (e.g., People v Collins, 438 Mich 8 (1991); People v Chapman, 425 Mich 245 (1986)) to argue the Court should not “uncouple” Article 1, § 11 from the Fourth Amendment absent a compelling reason.

5) Ineffective Assistance of Counsel

The majority’s remedy turned on Sixth Amendment doctrine:

  • People v LeBlanc, 465 Mich 575 (2002): Standard of review—mixed questions of fact and constitutional law; factual findings reviewed for clear error.
  • Strickland v Washington, 466 US 668 (1984): The two-prong performance and prejudice test. The Court held counsel’s performance was objectively unreasonable and prejudicial.
  • People v Hughes, 506 Mich 512 (2020): Cited both for (a) distinguishing plain-error review from ineffective-assistance review and (b) interpreting United States v Edwards as allowing reasonable delay when the search is already permissible.
  • People v Trakhtenberg, 493 Mich 38 (2012): Used to stress deficient “strategy” when choices are made after incomplete investigation; the majority suggested counsel failed to research relevant caselaw like Carr and Trudeau.

Legal Reasoning

  1. Step 1—Was there a “search”? The Court treated DNA testing of “effects” as an information-seeking occupation of constitutionally protected property. Under the trespass approach, that sufficed to establish a search without examining subjective/objective privacy expectations in pants worn in public or blood on the fabric.
  2. Step 2—Was the search reasonable without a warrant? The Court applied the per se rule from Katz v United States that warrantless searches are presumptively unreasonable, placing the burden on the State (citing Coolidge v New Hampshire, 403 US 443 (1971)) to show a “specifically established” exception. The State failed because:
    • Inventory search did not apply: DNA testing is neither standardized inventory procedure nor tied to inventory’s administrative/safety rationales.
    • Search incident to arrest did not apply: the arrest/detention was for an unrelated misdemeanor; under People v Carr and People v Trudeau (and consistent with Arizona v Gant), Michigan does not permit using custody for one offense as a platform to search for evidence of another offense without a warrant.
  3. Step 3—Was counsel ineffective? The Court held counsel’s failure to file a suppression motion was unreasonable because existing Michigan caselaw supported suppression and because counsel could have pursued suppression without abandoning fallback trial arguments. Prejudice was found because, without the DNA evidence, the prosecution’s case lacked physical linkage to the murder scene.

Impact

  • Operational rule for Michigan law enforcement: Forensic DNA testing of an arrestee’s clothing/effects held in jail custody is a “search” requiring a warrant or consent unless a genuine exception applies; “inventory” cannot be used as a pretext to convert safekeeping into forensic investigation.
  • Reaffirmation and modernization of Carr/Trudeau: The decision reinforces a Michigan-specific “same-offense” limitation: custody for one matter does not authorize warrantless evidence-gathering for a different offense.
  • Defense counsel obligations: The opinion signals that failing to litigate suppression of high-value forensic evidence—when supported by existing Michigan constitutional precedent—can satisfy both Strickland prongs, especially where the evidence is the principal physical link.
  • Doctrinal ripple effects: By leaning on Johnson v VanderKooi and the trespass approach, the Court supplies an alternative path to “search” findings in future property/effects cases, potentially reducing how often courts must litigate the contested boundary of “reasonable expectation of privacy,” an area highlighted by the dissent through cases like Carpenter v United States, 585 US 296 (2018) and Chatrie v United States, 609 US ___ (June 29, 2026).

Complex Concepts Simplified

  • “Search” (trespass approach): A search occurs when the government physically occupies or manipulates constitutionally protected property (“persons,” “houses,” “papers,” “effects/possessions”) to obtain information—regardless of whether the person expected privacy.
  • “Search” (Katz privacy approach): A search occurs if the government violates an actual expectation of privacy that society recognizes as reasonable.
  • Inventory search: An administrative cataloging of property when someone is booked into custody, justified by safekeeping, preventing theft/false claims, and institutional safety—not by investigation.
  • Search incident to arrest: A narrow warrant exception allowing officers to search an arrestee and the immediate area to find weapons, prevent escape, and (within limits) preserve evidence—here constrained by Michigan precedent when officers use custody for one offense to investigate another.
  • Ineffective assistance (Strickland): A defendant must show (1) counsel acted unreasonably compared to professional norms and (2) the error likely mattered—i.e., there’s a reasonable probability of a different outcome.
  • Ginther hearing: A Michigan evidentiary hearing to develop a factual record on an ineffective-assistance claim (named after People v Ginther, 390 Mich 436 (1973)).

Conclusion

People v Serges establishes that, under Const 1963, art 1, § 11, police forensic DNA testing of an arrestee’s clothing/effects—held in custody after booking—constitutes a search and is unreasonable without a warrant or consent when used to investigate an unrelated crime and when neither inventory nor search incident to arrest legitimately applies. The decision powerfully reasserts People v Carr and People v Trudeau as active constraints on leveraging custody for one matter into warrantless evidence-gathering for another. It also underscores a practical Sixth Amendment lesson: when a single piece of forensic evidence supplies the case’s physical nexus, failure to pursue a supported suppression motion can amount to constitutionally ineffective lawyering requiring reversal.