Lange v. California, 594 U.S. 295

Arthur Lange drove past a California Highway Patrol officer blaring music and honking; when the officer signaled him to stop, Lange drove a short distance into his driveway and into an attached garage instead of pulling over.
The officer followed Lange into the garage, observed signs of intoxication, administered field sobriety tests, and obtained a blood test showing BAC over three times the legal limit.
Lange was charged with misdemeanor DUI (and a noise infraction) and moved to suppress evidence obtained after the warrantless entry into his garage; California courts upheld the entry under a categorical "hot pursuit" rule for misdemeanors.
The State (and appointed amicus) argued that flight by a suspected misdemeanant always creates exigent circumstances permitting warrantless home entry; Lange argued the Fourth Amendment requires a case-specific exigency inquiry.
The Supreme Court vacated the California Court of Appeal judgment and held that pursuit of a fleeing misdemeanant does not categorically justify warrantless home entry; exigent-circumstances must be assessed case by case and the case was remanded for further proceedings.

Issue	Plaintiff's Argument (Lange)	Defendant's Argument (California / Amicus)	Held
Whether pursuit of a fleeing misdemeanant categorically authorizes warrantless entry into a home	No — flight alone is insufficient; exigent-circumstances must be shown case by case	Yes — flight itself always supplies exigency justifying entry	No categorical rule; exigency must be assessed under the totality of circumstances; flight may be a factor but is not automatically sufficient
Whether historical/common-law practice supports a categorical misdemeanor-pursuit exception	Common law did not recognize a blanket rule for misdemeanors; entries depended on circumstances	Santana and common-law practices support broad pursuit exception	Common-law evidence shows a felony-based exception and circumstance-specific misdemeanor rules; history does not support a categorical misdemeanor rule
Whether evidence obtained after a possibly unlawful entry must be suppressed	Suppress evidence if entry unlawful	(Some concurrences) argue exclusionary rule should not apply; State position varied	Majority remanded without resolving exclusionary-rule issue; Justice Thomas would bar exclusion (i.e., not require suppression); Court did not impose suppression ruling

United States v. Santana, 427 U.S. 38 (1976) (upheld warrantless entry in hot pursuit of a fleeing felon)
Riley v. California, 573 U.S. 373 (2014) (Fourth Amendment generally requires a warrant for home-entry searches)
Kentucky v. King, 563 U.S. 452 (2011) (exigent-circumstances exception permits warrantless entry when needs of law enforcement are compelling)
Welsh v. Wisconsin, 466 U.S. 740 (1984) (application of exigent-circumstances exception should be rare for minor offenses)
Brigham City v. Stuart, 547 U.S. 398 (2006) (warrantless entry permissible to render emergency aid or prevent imminent injury)
Missouri v. McNeely, 569 U.S. 141 (2013) (case-specific exigency inquiry; delay to obtain warrant may not always be unreasonable)
Payton v. New York, 445 U.S. 573 (1980) (firm constitutional protection of the home; warrant generally required for entry to effect an arrest)
Steagald v. United States, 451 U.S. 204 (1981) (warrant required to enter third party’s home absent consent or exigency)