ABA Supreme Court Preview: Case v. Montana

Case At A Glance

Petitioner William Trevor Case was convicted of assaulting a police officer in Montana. The assault charge arose from an armed, warrantless police entry into petitioner’s home when the police suspected that petitioner intended “suicide by cop.” Petitioner moved to suppress the evidence the police seized during the entry, arguing that the police lacked probable cause of an emergency to justify a warrantless entry. The Montana courts, however, found that even if the police lacked the traditional standard of probable cause, they had a “reasonable suspicion” that petitioner presented a suicide risk that satisfied the emergency-aid exception to the Fourth Amendment’s warrant requirement. Petitioner appealed to the U.S. Supreme Court, arguing that, to enter a home without a warrant to intervene in a perceived emergency, the police still must have probable cause that the emergency exists.

Case v. Montana
Docket No. 24-624

Argument Date: October 15, 2025
From: The Montana Supreme Court

by Brooks Holland
Gonzaga University School of Law, Spokane, WA

Issue

May the police enter a home without a search warrant and less than probable cause to intervene in a perceived emergency, or does the Fourth Amendment demand probable cause for the emergency-aid exception to the warrant requirement?

Facts

In September 2021, petitioner’s ex-girlfriend called 911 in Anaconda, Montana, to report that petitioner, an Army veteran, was behaving erratically and threatened to commit suicide. The ex-girlfriend further reported that petitioner said if the police intervened, he “would shoot them all too.” Four officers responded to this call as a “welfare check on a suicidal male.”

All of the responding officers knew petitioner and were familiar with his history of alcohol abuse, mental health issues, and prior incidents of suicide threats, including “suicide by cop” threats. Upon arrival at petitioner’s home, the officers looked through windows and did not see petitioner, blood, or any other sign of injury. The officers, however, noticed an empty handgun holster, beer cans, and a notepad that the officers thought might be a suicide note.

The officers waited roughly 40 minutes outside the home before deciding to enter. During this time, the officers shared their belief that petitioner was likely attempting “suicide by cop” and was waiting for them, rather than needing immediate medical aid. The officers considered calling petitioner’s family and even petitioner himself, but ultimately did not. After retrieving rifles and a ballistic shield, the officers entered petitioner’s home through the unlocked front door. The officers never sought a warrant during this time.

Inside the home, an officer encountered petitioner emerging from an upstairs closet with an outstretched arm holding a “dark object” that the officer later testified appeared to be a weapon. The officer’s body-cam video corroborated this testimony. The officer, in response, shot petitioner in the arm and abdomen. The officers subsequently recovered a handgun from a nearby laundry basket. Petitioner was arrested and charged with felony assault on a police officer.

Prior to trial, petitioner moved to suppress the handgun and other evidence from his home on the ground that the police did not have probable cause to enter his home without a warrant to deliver emergency aid. Petitioner acknowledged that an emergency can justify a warrantless entry, but argued this exception does not dispense with the requirement of probable cause that the emergency existed. At a hearing, the officers testified that they did not enter the home to shoot anybody, but rather, “to help people.” Yet, the officers also testified that the likely presence of weapons necessitated a “heightened” police response for officer safety.

The trial court rejected petitioner’s argument and denied the motion to suppress. Petitioner proceeded to trial, and a jury convicted him. Petitioner appealed to the Montana Supreme Court, arguing that the trial court should have excluded the evidence from his home.

In a divided 4–3 decision, the Montana Supreme Court rejected petitioner’s position that the emergency-aid exception to the warrant requirement necessitates probable cause of an emergency. See State v. Case, 553 P.3d 985 (Mont. 2024). The majority deemed that “probable cause” is “superfluous” when a police officer is “acting in a caretaker’s capacity” and the officer’s “reasons for a warrantless entry” are “totally divorced” from the investigation of crime. The dissent, by contrast, opined that the U.S. Supreme Court already has rejected a stand-alone “community caretaker” exception to the warrant requirement, and the well-established “exigency” exception requires probable cause of the exigency to obviate the need for a warrant.

Petitioner pursued a writ of certiorari in the U.S. Supreme Court. The Supreme Court granted the writ on June 2, 2025.

Case Analysis

The Fourth Amendment to the U.S. Constitution contains two clauses. The first clause provides that government searches and seizures must be “reasonable.” Under the second clause, a court may issue a search warrant only on a showing of probable cause that a crime was committed and the person or place to be searched holds relevant evidence. From these two clauses, probable cause is a traditional, but not the exclusive, standard for whether a search or seizure is reasonable. For instance, sometimes only “reasonable suspicion” is required.

Probable cause and reasonable suspicion can sound similar in judicial descriptions, as both standards ask whether the information available to the police objectively justified the police action as reasonable. But the Court long ago held that reasonable suspicion is a lower standard of proof than probable cause, and typically can justify only specific, limited police action short of a full-blown search or seizure, such as a stop-and-frisk or a traffic stop.

The primary question in petitioner’s appeal is whether the police needed probable cause to enter petitioner’s home without a warrant, or instead only a reasonable suspicion, because the police were intervening in an emergency and not investigating crime. Petitioner argues that a probable cause requirement in this context is supported by first principles, precedent, the common law, and the “relevant interests.”

Beginning with first principles, petitioner emphasizes that a person’s freedom within the home is “the archetype of privacy protection secured by the Fourth Amendment.” Precedent consistently elevates this privacy of the home as paramount under the Fourth Amendment. This precedent thus presumptively demands two baseline conditions to a reasonable search of the home: probable cause to search and a judicial warrant authorizing the search.

Petitioner acknowledges that precedent does recognize certain exceptions to the warrant requirement, such as “exigent circumstances.” This exception adapts the Fourth Amendment paradigm for reasonable searches of homes when circumstances present a need “so compelling that [a] warrantless search is objectively reasonable.” Petitioner emphasizes, however, that the Court already has rejected a standalone “community caretaker” exception in a case that also involved a perceived suicide risk. See Caniglia v. Strom, 593 U.S. 194 (2021).

Therefore, in petitioner’s view, any emergency- aid exception operates as an iteration of exigent circumstances. The exigent circumstances exception dispenses only with the warrant requirement. The police still must demonstrate probable cause of the exigency to invoke this exception. Probable cause properly confines judicial review to objective, evidence-based justifications for a warrantless entry, which should not turn on the officers’ subjective intentions.

Moreover, petitioner reinforces that, according to established precedent, reasonable suspicion can justify only limited-scope police action, such as a stop-and-frisk or a traffic stop, and not a full search of the core zone of privacy protected by the Fourth Amendment—the home. In petitioner’s view, respondent is seeking an unprecedented double-exception for emergency aid cases: an exception from the warrant requirement, and an exception from the probable cause requirement, too.

Respondent challenges petitioner’s take on Fourth Amendment jurisprudence. Respondent repeatedly emphasizes that the lodestar of the Fourth Amendment is reasonableness, not necessarily a warrant or even probable cause. The Framers added the warrant clause, respondent maintains, to limit government power to abuse the warrant process. The reasonableness clause, however, alone defines the Fourth Amendment right.

Respondent thus defines the issue as a pure reasonableness inquiry. Respondent largely avoids the term “reasonable suspicion” from the stop-and-frisk context as the desired standard, instead characterizing the proper standard for emergencies as an “objectively reasonable belief.” To respondent, “probable cause” and “reasonable suspicion” are terms of art that are “‘rooted’ in ‘the criminal investigatory context,’” and therefore are “‘unhelpful’ when analyzing the reasonableness of law enforcement’s noncriminal ‘administrative functions.’”

Reinforcing this point from precedent on exigent circumstances, respondent claims that, contrary to petitioner’s position, the Court “has declined to require probable cause for any of these exigencies,” instead asking only whether the officer “reasonably believed” the officer faced an emergency. In a particular emergency context when the police acted to protect people from harm, respondent adds, the Court has already held that courts should inquire only whether the police intervention was objectively reasonable. See Brigham City v. Stuart, 547 U.S. 398 (2006). The Montana Supreme Court, respondent asserts, took exactly this approach, and did not adopt an open-ended reasonable suspicion standard for warrantless searches of homes.

The parties also debate prevailing common practices when the Fourth Amendment was adopted as evidence for their positions. Petitioner cites to the “affray” rule at common law. Under this rule, a constable could enter a home non- consensually only to address an “absolute necessity,” which could include an “affray” in the home. But this authority limited entries to cases where the constable could see or hear the affray directly. This common-law requirement of direct observation for lawful entry, petitioner explains, equates to a probable cause standard today.

Respondent, in turn, delivers an exegesis on the history of police entries into homes, working from the pre- Norman conquest “hue and cry” doctrine to the King’s Bench and English scholars such as Blackstone, Coke, and Hale. From this study, respondent offers two reads on the common law: (1) “the common law reflects a flexible reasonableness approach, allowing warrantless entries, in some circumstances based only on mere suspicion,” and (2) “in the noncriminal, noninvestigatory context, the common-law doctrine of necessity permitted both officers and private citizens to break into homes to save life or property.”

Petitioner adds that even if the Court treats this issue as an open-ended reasonableness question, the balance of interests favors probable cause as the proper standard to govern this police action. Probable cause, petitioner reminds, remains a flexible and practical standard, not a scientific test. The police will retain ample authority to act in the face of a real emergency without sacrificing the privacy of the home under a lower standard. Further, probable cause will objectively constrain the police from employing an alleged emergency as a pretext for criminal investigation when they lack the otherwise necessary probable cause and a warrant.

Petitioner additionally claims that probable cause will help to lessen the risk of conflict and harm to both officers and residents when the police forcibly enter with less information than probable cause assures. This concern is particularly acute for people with mental health conditions, petitioner emphasizes, and in this era of “swatting” incidents and digital harassment. Petitioner stresses, “[l]aw-abiding citizens should not lose Fourth Amendment protections just because they ‘struggle with suicide and depression.’” Petitioner thus explores options for “wellness checks” short of a forcible police entry with less than probable cause.

Respondent counters that a rigid probable cause standard will thwart the police from acting right when intervention is most needed—during an uncertain emergency situation when someone may need help. Invoking the risk of the most dire outcomes, respondent asserts that petitioner’s position “would destroy the emergency-aid exigent circumstance since officers cannot obtain either probable cause or warrants for a medical welfare check,” and petitioner’s “preferred regime will turn American homes into ‘the place where’ citizens who need urgent medical help ‘died alone and in agony.’” These risks illustrate, in respondent’s view, why probable cause is not the appropriate standard for balancing emergency-aid needs with privacy interests.

Finally, both parties litigate the facts under their preferred legal standard. Petitioner argues a lack of probable cause for any emergency, citing facts such as the 40-minute delay and officer statements at the scene before the police entered, armed for confrontation, not assistance. Respondent defends the objective reasonableness of this intervention, citing the 911 report from a known person with details of a threatened suicide, along with the officers’ training and experience, personal knowledge of petitioner, and observations at the home.

Significance

This case invites the Supreme Court to revisit whether the usual Fourth Amendment constraints apply to the police when, instead of investigating crime, the police are acting as “community caretakers,” in the classic public role of rescuing someone’s cat from a tree. Conceivably, the Court could decide the case on the facts regardless of which standard applies, which would be a more narrow decision. But the larger issue the parties press is the precise legal standard that should govern a warrantless police entry into a home to address a perceived emergency: probable cause, reasonable suspicion, or “objective reasonableness.”

As respondent argues, the ability of police to deliver needed aid in an emergency may be unduly hampered if the police first must satisfy probable cause, the same evidentiary standard required for criminal investigations. Respondent avoids arguing for the much lower “reasonable suspicion” standard from the stop-and-frisk context, but does not definitively explain where “objective reasonableness” falls in between these two more familiar standards.

Moreover, as petitioner observes, the line between an emergency and an investigation can be difficult for courts to regulate, inviting uncertain new litigation in these cases if the Court adopts a more open-ended reasonableness test. Furthermore, an emergency-aid exception even from probable cause, and not only a warrant, could establish a sizable loophole for police to evade the Fourth Amendment’s fundamental protection of privacy in the home.

The numerous amicus curiae briefs highlight the potential significance to the Court’s decision, and most of these briefs weigh in favor of the petitioner’s position. These amicus all presage risks to the sanctity of the home from unreasonable governmental intrusion if the police can enter under a more forgiving legal test by invoking a claim of emergency intervention. The amici, however, focus on different interests that this emergency authority could impact.

For example, a group of aligned interests including the Conservative Legal Defense Fund, Gun Owners of America, and other groups challenges Montana’s position as jeopardizing not only privacy in the home, but also other rights exercised by law-abiding persons in the home, such as Second Amendment rights. In this group’s view, the law should not enable the paradox where persons suspected of crime have greater privacy in their homes. The LONANG Institute expands on these concerns, arguing that Montana’s position undermines fundamental property rights, established by “the Laws of Nature and Nature’s God.”

The Cato Institute emphasizes the privacy interests inherent in the home and highlights the dangers of warrantless entries with historical and contemporary narratives about violent and tragic encounters that have resulted from police entering the wrong house or reacting to a homeowner’s self-defense actions. A collection of privacy groups share a different privacy lens, expressing concern for digital privacy if the Court lowers the standard for home intrusions. In this group’s view, modern technologies such as phones and tablets have become a digital “home” in privacy interests and also a place where the police may want access to assess a perceived emergency.

Other groups such as the National and Montana Associations of Criminal Defense Lawyers, the American Civil Liberties Union, the Constitutional Accountability Center, and the Rutherford Institute all press the importance of probable cause to limit governmental power. Such a broad emergency exception, these interest groups worry, may be applied selectively and ultimately could swallow the home-privacy rule or invite pretext emergencies. The probable cause standard provides a predictable and uniform check on these potential abuses.

A group of mental health experts takes no sides but provides the Court with an overview of the challenges and experiences for law enforcement when responding to mental health crises, noting that the police have increasingly become de facto mental health crisis first responders, often without training. These experts showcase best practices to reduce harm.

Conclusion

Because the Fourth Amendment is fundamentally grounded in “reasonable” constraints on governmental intrusions into privacy, Fourth Amendment cases can reveal a lot about justices’ views on this important security–liberty balance. This balance is all the more salient during times when law enforcement norms may be shifting significantly. See, e.g., Noem v. Perdomo, No. 25A169, 606 U.S. (Sept. 8, 2025). This case positions an individual’s fundamental expectation of privacy in the home against the community’s interest in effective emergency aid, including from the police. The Court’s oral argument and decision may signal whether a majority shares the concerns of the parties or the amici, or will strike a different balance.