Utah v. Strieff, 579 U.S. 232

Background

Narcotics detective surveilled a Salt Lake residence after an anonymous tip and saw frequent short visits suggesting drug dealing.
Officer Fackrell stopped Edward Strieff minutes after he left the house, asked questions, and requested ID without reasonable suspicion (State conceded lack of reasonable suspicion).
Dispatcher reported an outstanding pre-existing arrest warrant for Strieff for a traffic violation; Fackrell arrested and searched him and found methamphetamine and paraphernalia.
Strieff moved to suppress; trial court and Utah Court of Appeals admitted evidence; Utah Supreme Court reversed, excluding it as tainted by the unlawful stop.
U.S. Supreme Court granted certiorari to decide whether discovery of a valid, pre-existing arrest warrant attenuates the taint from an unconstitutional investigatory stop.

Issues

Issue	Strieff's Argument	State's Argument	Held
Whether the attenuation doctrine can apply when the intervening circumstance is discovery of a pre-existing arrest warrant	A warrant discovered only because of an unlawful stop does not break the causal chain; only a defendant’s voluntary act (e.g., confession/consent) can attenuate	A valid, pre-existing, untainted warrant is an intervening circumstance that severs the connection between the illegal stop and later evidence	The discovery of the valid, pre-existing warrant attenuated the taint and made the evidence admissible
Application of Brown factors (temporal proximity, intervening circumstances, purpose/flagrancy) to these facts	The short time between stop and search and the fact the warrant discovery was foreseeable weigh against attenuation	The warrant is an independent intervening circumstance and officer misconduct was not purposeful or flagrant, so attenuation applies	Temporal proximity favors suppression, but intervening-circumstance and lack of flagrant misconduct dominate; evidence admissible
Whether officer’s misconduct was purposeful/flagrant enough to require suppression despite the warrant	The stop was the product of an investigative fishing expedition and thus sufficiently purposeful to require deterrence via exclusion	Officer made reasonable investigative choices and at most negligent mistakes; no systemic misconduct shown	Court found the officer’s conduct negligent, not flagrant or systemic, favoring admission
Policy: whether admitting evidence will encourage warrant-based dragnet stops	Admitting would incentivize stops to find warrants and enable widespread suspicionless seizures	Civil liability, Brown-factor analysis, and lack of evidence of such practices mitigate that risk	Court discounted the dragnet concern absent evidence of purposeful widespread misconduct; held admission permissible

Key Cases Cited

Brown v. Illinois, 422 U.S. 590 (1975) (sets three-factor attenuation test: temporal proximity, intervening circumstances, and purpose/flagrancy of misconduct)
Segura v. United States, 468 U.S. 796 (1984) (evidence obtained under an untainted warrant may be admitted when unlawful entry did not contribute to discovery)
Hudson v. Michigan, 547 U.S. 586 (2006) (exclusionary rule is a last resort; attenuation doctrine described)
Mapp v. Ohio, 367 U.S. 643 (1961) (exclusionary rule as remedy for Fourth Amendment violations)
Wong Sun v. United States, 371 U.S. 471 (1963) (fruit-of-the-poisonous-tree and when later statements are sufficiently distinguishable from prior illegality)
United States v. Leon, 468 U.S. 897 (1984) (warrant as judicial mandate and good-faith considerations)
Arizona v. Gant, 556 U.S. 332 (2009) (scope of search incident to arrest)
Davis v. United States, 564 U.S. 229 (2011) (balancing deterrence benefits against costs of exclusion)
Kaupp v. Texas, 538 U.S. 626 (2003) (temporal proximity: substantial time between unlawful act and evidence favors attenuation)
Nix v. Williams, 467 U.S. 431 (1984) (inevitable discovery doctrine)
Murray v. United States, 487 U.S. 533 (1988) (independent source doctrine)