Case v. Montana
The Supreme Court unanimously ruled that police entering a home to provide emergency aid do not need to satisfy the stricter 'probable cause' standard drawn from criminal-investigation law — they only need an objectively reasonable basis to believe someone inside faces serious danger.
The decision resolves a disagreement among lower courts and reaffirms a 2006 rule, while two justices wrote separately to flag the particular care officers should exercise when the emergency involves a mental-health crisis.
How it got here: A Montana trial court denied Case's motion to suppress and a jury convicted him; the Montana Supreme Court affirmed on community-caretaker grounds; Case asked the Supreme Court to review, and the Court agreed to hear it to resolve a split among lower courts.
The Case in Depth
What happened
William Case, a Montana man, called his ex-girlfriend and told her he was going to kill himself. She heard sounds she believed were a gun cocking and firing, then silence. She called 911, and three officers responded. Finding no answer at the door, they observed through windows an empty gun holster, beer cans, and what appeared to be a suicide note. The officers entered to render aid. Case was hiding in a closet and emerged holding an object that looked like a gun; an officer shot and wounded him. Case was later charged with assaulting a police officer and sought to have all evidence from the warrantless entry thrown out.
The question before the Court
When police enter a home without a warrant to help someone they believe may be in danger, must they meet the same "probable cause" standard used in criminal investigations?
The Court's answer
No — the Fourth Amendment's emergency-aid exception does not require police to have "probable cause," the standard applied in criminal investigations. The Court unanimously held that the 2006 Brigham City v. Stuart decision means exactly what it says: officers may enter a home without a warrant when they have an "objectively reasonable basis for believing" that an occupant is seriously injured or imminently threatened with serious injury. Probable cause is a standard rooted in the criminal-investigation context — built up case by case around the question of whether contraband or evidence of crime is likely present — and it would fit poorly in the non-criminal, life-saving setting of an emergency welfare call.
The officers here easily satisfied the Brigham City standard. They knew Case had a history of mental-health and alcohol problems and prior threats of suicide. His ex-girlfriend had just heard what sounded like a gun cocking and firing before the line went dead. At the house, they saw an empty holster, a notepad, and empty beer cans — and Case did not respond to their calls. Taken together, those facts gave the officers an objectively reasonable basis to believe Case had shot himself or was about to, and their decision to enter to prevent that result was reasonable under the Fourth Amendment.
Curious how the Court got there? See the step-by-step legal reasoning →
Why it matters
Police responding to welfare calls — reports of suicide, domestic emergencies, or sudden illness — can enter a home without a warrant as long as the facts give them an objectively reasonable belief that someone inside is in serious danger. They do not need evidence strong enough for an arrest. At the same time, their search inside the home is limited to what is reasonably needed to address the emergency.
What changes now
Case's conviction for assaulting a police officer stands. The evidence from the warrantless entry remains admissible. Going forward, police and lower courts across the country now have a uniform rule: emergency-aid entries are measured by "objectively reasonable basis for believing" serious harm exists — not probable cause and not mere reasonable suspicion. The ruling does not address how much force or how broad a search is permissible once officers are lawfully inside.
What this does not decide
The ruling does not determine what search or use of force is permissible after police have lawfully entered under the emergency-aid exception; the Court notes officers may not search beyond what is reasonably needed to address the emergency. It also does not decide whether de-escalation alternatives are ever constitutionally required before entry.
Concurrences and dissents
How the Justices voted
Majority (8). Justice Kagan (author), joined by Justice Roberts, Justice Thomas, Justice Alito, Justice Sotomayor, Justice Gorsuch, Justice Kavanaugh, and Justice Barrett.
Concurrence — Justice Sotomayor
Justice Sotomayor joined the majority fully but wrote to highlight the distinctive risks that arise when the emergency involves a mental-health crisis. Entering the home of someone in a psychiatric emergency can escalate danger for both the occupant and officers, and studies show that people with serious mental illness are far more likely to be killed during police interactions. She urged officers to consider de-escalation tactics — such as speaking from a distance, involving family members, or calling in crisis-trained specialists — before entering, and emphasized that the reasonableness of the manner of entry and subsequent conduct inside also remains subject to constitutional scrutiny.
Concurrence — Justice Gorsuch
Justice Gorsuch agreed with the holding but wrote to explain what he sees as its deeper legal foundation: the common law, not merely judicial intuition about what seems reasonable. He traced a historical property-law doctrine allowing private citizens — and, by extension, government officers — to enter another's property to prevent serious physical harm, with liability depending on the reasonableness of the actor's judgment at the time. He argued this common-law grounding gives the emergency-aid exception a firmer basis than a simple majority-vote conclusion that such entries are 'reasonable,' and criticized the Court's older 'reasonable expectations of privacy' framework as insufficiently tied to law. Read the full concurrence →
How the Court got there
The legal reasoning, step by step
- The Fourth Amendment generally requires police to get a warrant before entering a home, because the home sits at the core of the Amendment's protection. But the warrant requirement has recognized exceptions, one of which allows officers to enter without a warrant to render emergency assistance to an occupant in serious danger — first approved in Brigham City v. Stuart (2006).
- Brigham City set the standard for emergency-aid entries as whether officers had 'an objectively reasonable basis for believing' an occupant was seriously injured or imminently threatened with such injury. This is a distinct standard — lower courts disagreed whether it effectively meant 'probable cause,' the familiar criminal-law threshold, or something closer to the weaker 'reasonable suspicion' used for brief street stops.
- The Court rejected the probable-cause reading. Probable cause evolved entirely within the criminal-investigation context — through decades of cases asking whether police had sufficient reason to believe contraband or evidence of crime would be found. That body of law does not translate cleanly to a non-criminal, life-saving situation, and there is no good reason to force it to do so.
- The Montana Supreme Court had applied its own 'community caretaker' doctrine, which allowed home entry when officers had 'specific and articulable facts' giving them reason to 'suspect' someone needed help. That language tracks the 'reasonable suspicion' standard for street stops — a lower bar inappropriate for home entries. The Court had also already warned in Caniglia v. Strom (2021) against using 'community caretaking' language in the home-entry context.
- Applying the correct Brigham City standard to the full picture of circumstances — Case's mental-health and alcohol history known to officers, his ex-girlfriend's account of the call (suicide threats, sounds of a gun cocking and firing, sudden silence), the empty holster and apparent suicide note visible through windows, and Case's failure to respond — the officers had an objectively reasonable basis to believe Case had already shot himself or would do so. Their decision to enter was reasonable, even accounting for the risk that entry could provoke a confrontation.
Doctrinal impact
Cases affected by this decision
Reaffirms Brigham City v. Stuart (547 U.S. 398)
The 2006 'objectively reasonable basis' standard for emergency home entries is confirmed as the governing test, unchanged.
Reaffirms Caniglia v. Strom (593 U.S. 194)
The 2021 bar on using broad 'community caretaking' rationale for warrantless home entries is reaffirmed and applied to reject Montana's framing.
Reaffirms Michigan v. Fisher (558 U.S. 45)
The 2009 application of the Brigham City standard to a scene of apparent violence and danger is reaffirmed as consistent with today's ruling.