`(Slip Opinion)
`
`
`
` OCTOBER TERM, 2018
`
`
`Syllabus
`
`1
`
` NOTE: Where it is feasible, a syllabus (headnote) will be released, as is
`
`
`
` being done in connection with this case, at the time the opinion is issued.
`
`
`
` The syllabus constitutes no part of the opinion of the Court but has been
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` prepared by the Reporter of Decisions for the convenience of the reader.
`
` See United States v. Detroit Timber & Lumber Co., 200 U. S. 321, 337.
`
`
`SUPREME COURT OF THE UNITED STATES
`
`
`
` Syllabus
`
`MITCHELL v. WISCONSIN
`
`CERTIORARI TO THE SUPREME COURT OF WISCONSIN
`
` No. 18–6210. Argued April 23, 2019—Decided June 27, 2019
`
` Petitioner Gerald Mitchell was arrested for operating a vehicle while
`
`
`intoxicated after a preliminary breath test registered a blood alcohol
`concentration (BAC) that was triple Wisconsin’s legal limit for driv-
` ing. As is standard practice, the arresting officer drove Mitchell to a
`
`police station for a more reliable breath test using evidence-grade
`equipment. By the time Mitchell reached the station, he was too le-
` thargic for a breath test, so the officer drove him to a nearby hospital
`
`for a blood test. Mitchell was unconscious by the time he arrived at
`
` the hospital, but his blood was drawn anyway under a state law that
`
`presumes that a person incapable of withdrawing implied consent to
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`BAC testing has not done so. The blood analysis showed Mitchell’s
`
`BAC to be above the legal limit, and he was charged with violating
`two drunk-driving laws. Mitchell moved to suppress the results of
`the blood test on the ground that it violated his Fourth Amendment
`right against “unreasonable searches” because it was conducted
`without a warrant. The trial court denied the motion, and Mitchell
`
`was convicted. On certification from the intermediate appellate
`
`court, the Wisconsin Supreme Court affirmed the lawfulness of
`
`Mitchell’s blood test.
`Held: The judgment is vacated, and the case is remanded.
`2018 WI 84, 383 Wis. 2d 192, 914 N. W. 2d 151, vacated and remanded.
`JUSTICE ALITO, joined by THE CHIEF JUSTICE, JUSTICE BREYER, and
`JUSTICE KAVANAUGH, concluded that when a driver is unconscious
`
`and cannot be given a breath test, the exigent-circumstances doctrine
`
`generally permits a blood test without a warrant. Pp. 5–17.
`
`
`(a) BAC tests are Fourth Amendment searches. See Birchfield v.
`
`
`
`North Dakota, 579 U. S. ___, ___. A warrant is normally required for
`
`a lawful search, but there are well-defined exceptions to this rule, in-
`cluding the “exigent circumstances” exception, which allows warrant-
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`
`
`

`

`2
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`
`MITCHELL v. WISCONSIN
`
`
`Syllabus
`
`less searches “to prevent the imminent destruction of evidence.” Mis-
`
`souri v. McNeely, 569 U. S. 141, 149. In McNeely, this Court held
`that the fleeting nature of blood-alcohol evidence alone was not
`enough to bring BAC testing within the exigency exception. Id., at
`
`
`156. But in Schmerber v. California, 384 U. S. 757, the dissipation of
`BAC did justify a blood test of a drunk driver whose accident gave po-
`lice other pressing duties, for then the further delay caused by a war-
`rant application would indeed have threatened the destruction of ev-
`
`idence. Like Schmerber, unconscious-driver cases will involve a
`
`heightened degree of urgency for several reasons. And when the
`
`driver’s stupor or unconsciousness deprives officials of a reasonable
`opportunity to administer a breath test using evidence-grade equip-
`
`ment, a blood test will be essential for achieving the goals of BAC
`
`testing. Pp. 5–7.
`
`
`(b) Under the exigent circumstances exception, a warrantless
`search is allowed when “ ‘there is compelling need for official action
`
`and no time to secure a warrant.’ ” McNeely, 569 U. S., at 149. Pp. 7–
`
`
`16.
`
`
`
`(1) There is clearly a “compelling need” for a blood test of drunk-
`
`driving suspects whose condition deprives officials of a reasonable
`
`opportunity to conduct a breath test. First, highway safety is a vital
`
`public interest—a “compelling” and “paramount” interest, Mackey v.
`
`Montrym, 443 U. S. 1, 17–18. Second, when it comes to promoting
`that interest, federal and state lawmakers have long been convinced
`that legal limits on a driver’s BAC make a big difference. And there
`
`is good reason to think that such laws have worked. Birchfield, 579
`U. S., at ___. Third, enforcing BAC limits obviously requires a test
`that is accurate enough to stand up in court. Id., at ___. And such
`
`
`
`testing must be prompt because it is “a biological certainty” that
`
`“[a]lcohol dissipates from the bloodstream,” “literally disappearing by
`the minute.” McNeely, 569 U. S., at 169 (ROBERTS, C. J., concurring).
`
`
`Finally, when a breath test is unavailable to promote the interests
`served by legal BAC limits, “a blood draw becomes necessary.” Id., at
`
`170. Pp. 9–12.
`
`(2) Schmerber demonstrates that an exigency exists when (1)
`BAC evidence is dissipating and (2) some other factor creates press-
`ing health, safety, or law enforcement needs that would take priority
`
`over a warrant application. Because both conditions are met when a
`
`
`drunk-driving suspect is unconscious, Schmerber controls. A driver’s
`
`unconsciousness does not just create pressing needs; it is itself a med-
`
`ical emergency. In such a case, as in Schmerber, an officer could
`
`
`“reasonably have believed that he was confronted with an emergen-
`cy.” 384 U. S., at 771. And in many unconscious-driver cases, the ex-
`igency will be especially acute. A driver so drunk as to lose con-
`
`
`
`
`

`

`
`
`3
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`
`Cite as: 588 U. S. ____ (2019)
`
`
`Syllabus
`sciousness is quite likely to crash, giving officers a slew of urgent
`tasks beyond that of securing medical care for the suspect—tasks
`
`that would require them to put off applying for a warrant. The time
`needed to secure a warrant may have shrunk over the years, but it
`has not disappeared; and forcing police to put off other urgent tasks
`for even a relatively short period of time may have terrible collateral
`
`costs. Pp. 12–16.
`
`(c) On remand, Mitchell may attempt to show that his was an unu-
`sual case, in which his blood would not have been drawn had police
`not been seeking BAC information and police could not have reason-
`
`
`ably judged that a warrant application would interfere with other
`pressing needs or duties. Pp. 16–17.
`JUSTICE THOMAS would apply a per se rule, under which the natural
`
`metabolization of alcohol in the blood stream “creates an exigency
`
`once police have probable cause to believe the driver is drunk,” re-
`gardless of whether the driver is conscious. Missouri v. McNeely, 569
`
`U. S. 141, 178 (THOMAS, J., dissenting). Pp. 1–4.
`ALITO, J., announced the judgment of the Court and delivered an
`
`opinion, in which ROBERTS, C. J., and BREYER and KAVANAUGH, JJ.,
`
`joined. THOMAS, J., filed an opinion concurring in the judgment. SO-
`TOMAYOR, J., filed a dissenting opinion, in which GINSBURG and KAGAN,
`JJ., joined. GORSUCH, J., filed a dissenting opinion.
`
`
`
`

`

`
`
`
`
` Cite as: 588 U. S. ____ (2019)
`
`
`Opinion of ALITO, J.
`
`1
`
` NOTICE: This opinion is subject to formal revision before publication in the
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`
`
`
` preliminary print of the United States Reports. Readers are requested to
`
` notify the Reporter of Decisions, Supreme Court of the United States, Wash-
`
` ington, D. C. 20543, of any typographical or other formal errors, in order
`
`
` that corrections may be made before the preliminary print goes to press.
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`
`
`
`SUPREME COURT OF THE UNITED STATES
`
`
`
`_________________
`
` No. 18–6210
`_________________
` GERALD P. MITCHELL, PETITIONER v. WISCONSIN
`ON WRIT OF CERTIORARI TO THE SUPREME COURT OF
`
`WISCONSIN
`[June 27, 2019]
`JUSTICE ALITO announced the judgment of the Court
`and delivered an opinion, in which THE CHIEF JUSTICE,
`JUSTICE BREYER, and JUSTICE KAVANAUGH join.
`In this case, we return to a topic that we have addressed
`
`
`twice in recent years: the circumstances under which a
`police officer may administer a warrantless blood alcohol
`concentration (BAC) test to a motorist who appears to
`have been driving under the influence of alcohol. We have
`previously addressed what officers may do in two broad
`categories of cases. First, an officer may conduct a BAC
`
`test if the facts of a particular case bring it within the
`exigent-circumstances exception to the Fourth Amend-
`
`ment’s general requirement of a warrant. Second, if an
`officer has probable cause to arrest a motorist for drunk
`driving, the officer may conduct a breath test (but not a
`blood test) under the rule allowing warrantless searches of
`a person incident to arrest.
`
`Today, we consider what police officers may do in a
`narrow but important category of cases: those in which the
`
`driver is unconscious and therefore cannot be given a
`breath test.
`In such cases, we hold, the exigent-
`circumstances rule almost always permits a blood test
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`
`
`

`

`2
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`
`
`
` MITCHELL v. WISCONSIN
`
`Opinion of ALITO, J.
`
`without a warrant. When a breath test is impossible,
`
`enforcement of the drunk-driving laws depends upon the
`administration of a blood test. And when a police officer
`
`encounters an unconscious driver, it is very likely that the
`driver would be taken to an emergency room and that his
`blood would be drawn for diagnostic purposes even if the
`police were not seeking BAC information. In addition,
`police officers most frequently come upon unconscious
`
`drivers when they report to the scene of an accident, and
`under those circumstances, the officers’ many responsibili-
`
`ties—such as attending to other injured drivers or passen-
`gers and preventing further accidents—may be incompati-
`ble with the procedures that would be required to obtain a
`warrant. Thus, when a driver is unconscious, the general
`rule is that a warrant is not needed.
`I
`A
`In Birchfield v. North Dakota, 579 U. S. ___ (2016), we
`
`recounted the country’s efforts over the years to address
`
`the terrible problem of drunk driving. Today, “all States
`have laws that prohibit motorists from driving with a
`[BAC] that exceeds a specified level.” Id., at ___ (slip op.,
`at 2). And to help enforce BAC limits, every State has
`passed what are popularly called implied-consent laws.
`
`Ibid. As “a condition of the privilege of ” using the public
`
`roads, these laws require that drivers submit to BAC
`
`testing “when there is sufficient reason to believe they are
`
` violating the State’s drunk-driving laws.” Id., at ___, ___
`(slip op., at 2, 6).
`Wisconsin’s implied-consent law is much like those of
`
`the other 49 States and the District of Columbia. It deems
`drivers to have consented to breath or blood tests if an
`officer has reason to believe they have committed one of
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`
`
`
`

`

`3
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`Cite as: 588 U. S. ____ (2019)
`
`
`Opinion of ALITO, J.
`several drug- or alcohol-related offenses.1 See Wis. Stat.
`
`§§343.305(2), (3). Officers seeking to conduct a BAC test
`
`must read aloud a statement declaring their intent to
`administer the test and advising drivers of their options
`
`and the implications of their choice. §343.305(4). If a
`
`driver’s BAC level proves too high, his license will be
`
`suspended; but if he refuses testing, his license will be
`
`revoked and his refusal may be used against him in court.
`See ibid. No test will be administered if a driver refuses—
`or, as the State would put it, “withdraws” his statutorily
`presumed consent. But “[a] person who is unconscious or
`
`otherwise not capable of withdrawing consent is presumed
`§343.305(3)(b). See also
`not to have” withdrawn it.
`
`§§343.305(3)(ar)1–2. More than half the States have
`provisions like this one regarding unconscious drivers.
`B
`
`The sequence of events that gave rise to this case began
`when Officer Alexander Jaeger of the Sheboygan Police
`
`Department received a report that petitioner Gerald
`
`Mitchell, appearing to be very drunk, had climbed into a
`van and driven off. Jaeger soon found Mitchell wandering
`near a lake. Stumbling and slurring his words, Mitchell
`
`could hardly stand without the support of two officers.
`Jaeger judged a field sobriety test hopeless, if not danger-
`ous, and gave Mitchell a preliminary breath test. It regis-
`tered a BAC level of 0.24%, triple the legal limit for driv-
`ing in Wisconsin. Jaeger arrested Mitchell for operating a
`
`
`——————
`1Wisconsin also authorizes BAC testing of drivers involved in acci-
`
` dents that cause significant bodily harm, with or without probable
`
` cause of drunk driving. See Wis. Stat. §343.305(3)2 (2016). We do not
`address those provisions. And while Wisconsin’s and other implied-
`
`
` consent laws permit urine tests, those tests are less common, see
`Birchfield v. North Dakota, 579 U. S. ___, ___, n. 1 (2016) (slip op., at 6,
`
` n. 1), and we do not consider them here.
`
`
`
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`

`

`4
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` MITCHELL v. WISCONSIN
`
`Opinion of ALITO, J.
`
`vehicle while intoxicated and, as is standard practice,
`
`
`drove him to a police station for a more reliable breath test
`using better equipment.
`On the way, Mitchell’s condition continued to deterio-
`
`rate—so much so that by the time the squad car had
`
`reached the station, he was too lethargic even for a breath
`
`test. Jaeger therefore drove Mitchell to a nearby hospital
`for a blood test; Mitchell lost consciousness on the ride
`
`over and had to be wheeled in. Even so, Jaeger read aloud
`to a slumped Mitchell the standard statement giving
`
`drivers a chance to refuse BAC testing. Hearing no re-
`sponse, Jaeger asked hospital staff to draw a blood sam-
`ple. Mitchell remained unconscious while the sample was
`
`taken, and analysis of his blood showed that his BAC,
`
`about 90 minutes after his arrest, was 0.222%.
`Mitchell was charged with violating two related drunk-
`
`
`driving provisions. See §§346.63(1)(a), (b). He moved to
`suppress the results of the blood test on the ground that it
`violated his Fourth Amendment right against “unreason-
`able searches” because it was conducted without a warrant.
`
`Wisconsin chose to rest its response on the notion that its
`
`implied-consent law (together with Mitchell’s free choice to
`
` drive on its highways) rendered the blood test a consensual
`
`one, thus curing any Fourth Amendment problem. In the
`
`end, the trial court denied Mitchell’s motion to suppress,
`and a jury found him guilty of the charged offenses. The
`
`intermediate appellate court certified two questions to the
`
`Wisconsin Supreme Court: first, whether compliance with
`
`the State’s implied-consent law was sufficient to show that
`
`Mitchell’s test was consistent with the Fourth Amendment
`and, second, whether a warrantless blood draw from an
`
`unconscious person violates the Fourth Amendment. See
`2018 WI 84, ¶15, 383 Wis. 2d 192, 202–203, 914 N. W. 2d
`151, 155–156 (2018). The Wisconsin Supreme Court
`affirmed Mitchell’s convictions, and we granted certiorari,
`586 U. S. ___ (2019), to decide “[w]hether a statute author-
`
`
`
`

`

`
`
`
`
` Cite as: 588 U. S. ____ (2019)
`
`
`Opinion of ALITO, J.
`izing a blood draw from an unconscious motorist provides
`an exception to the Fourth Amendment warrant require-
`ment,” Pet. for Cert. ii.
`
`5
`
`
`
`
`II
`
`
`In considering Wisconsin’s implied-consent law, we do
`not write on a blank slate. “Our prior opinions have re-
`ferred approvingly to the general concept of implied-
`consent laws that impose civil penalties and evidentiary
`consequences on motorists who refuse to comply.” Birch-
`
`field, 579 U. S., at ___ (slip op., at 36). But our decisions
`have not rested on the idea that these laws do what their
`
`popular name might seem to suggest—that is, create
`actual consent to all the searches they authorize. Instead,
`we have based our decisions on the precedent regarding
`the specific constitutional claims in each case, while keep-
`
`ing in mind the wider regulatory scheme developed over
`the years to combat drunk driving. That scheme is cen-
`tered on legally specified BAC limits for drivers—limits
`enforced by the BAC tests promoted by implied-consent
`laws.
`
`Over the last 50 years, we have approved many of the
`defining elements of this scheme. We have held that
`
`forcing drunk-driving suspects to undergo a blood test
`does not violate their constitutional right against self-
`
`incrimination. See Schmerber v. California, 384 U. S. 757,
`
`
`765 (1966). Nor does using their refusal against them in
`
`
`court. See South Dakota v. Neville, 459 U. S. 553, 563
`(1983). And punishing that refusal with automatic license
`
`revocation does not violate drivers’ due process rights if
`they have been arrested upon probable cause, Mackey v.
`Montrym, 443 U. S. 1 (1979); on the contrary, this kind of
`summary penalty is “unquestionably legitimate.” Neville,
`supra, at 560.
`
`These cases generally concerned the Fifth and Four-
`teenth Amendments, but motorists charged with drunk
`
`
`
`

`

`
`
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`
`
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` MITCHELL v. WISCONSIN
`
`Opinion of ALITO, J.
`
`driving have also invoked the Fourth Amendment’s ban on
`“unreasonable searches” since BAC tests are “searches.”
`See Birchfield, 579 U. S., at ___ (slip op., at 14). Though
`our precedent normally requires a warrant for a lawful
`search, there are well-defined exceptions to this rule. In
`Birchfield, we applied precedent on the “search-incident-
`to-arrest” exception to BAC testing of conscious drunk-
`driving suspects. We held that their drunk-driving ar-
`rests, taken alone, justify warrantless breath tests but not
`
`blood tests, since breath tests are less intrusive, just as
`informative, and (in the case of conscious suspects) readily
`available. Id., at ___ (slip op., at 35).
`
`We have also reviewed BAC tests under the “exigent
`circumstances” exception—which, as noted, allows war-
`rantless searches “to prevent the imminent destruction of
`
`evidence.” Missouri v. McNeely, 569 U. S. 141, 149 (2013).
`
`In McNeely, we were asked if this exception covers BAC
`
`testing of drunk-driving suspects in light of the fact that
`blood-alcohol evidence is always dissipating due to “natu-
`
`ral metabolic processes.” Id., at 152. We answered that
`the fleeting quality of BAC evidence alone is not enough.
`
`Id., at 156. But in Schmerber it did justify a blood test of
`
`a drunk driver who had gotten into a car accident that
`
`gave police other pressing duties, for then the “further
`delay” caused by a warrant application really “would have
`threatened the destruction of evidence.” McNeely, supra,
`at 152 (emphasis added).
`
`Like Schmerber, this case sits much higher than
`
`McNeely on the exigency spectrum. McNeely was about
`the minimum degree of urgency common to all drunk-
`driving cases. In Schmerber, a car accident heightened
`that urgency. And here Mitchell’s medical condition did
`just the same.
`
`Mitchell’s stupor and eventual unconsciousness also
`
`deprived officials of a reasonable opportunity to adminis-
`
`ter a breath test. To be sure, Officer Jaeger managed to
`
`6
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`

`

`7
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` Cite as: 588 U. S. ____ (2019)
`
`
`Opinion of ALITO, J.
`conduct “a preliminary breath test” using a portable ma-
`
`chine when he first encountered Mitchell at the lake. App.
`
`to Pet. for Cert. 60a. But he had no reasonable opportunity
`
`to give Mitchell a breath test using “evidence-grade breath
`Birchfield, 579 U. S., at ___
`testing machinery.”
`(SOTOMAYOR, J., concurring in part and dissenting in part)
`(slip op., at 10). As a result, it was reasonable for Jaeger
`to seek a better breath test at the station; he acted with
`reasonable dispatch to procure one; and when Mitchell’s
`condition got in the way, it was reasonable for Jaeger to
`pursue a blood test. As JUSTICE SOTOMAYOR explained in
`her partial dissent in Birchfield:
`“There is a common misconception that breath tests
`
`are conducted roadside, immediately after a driver is
`arrested. While some preliminary testing is conducted
`roadside, reliability concerns with roadside tests con-
`
`fine their use in most circumstances to establishing
`probable cause for an arrest. . . . The standard eviden-
`tiary breath test is conducted after a motorist is ar-
`rested and transported to a police station, governmen-
`tal building, or mobile testing facility where officers
`can access reliable, evidence-grade breath testing ma-
`chinery.” Id., at ___ (slip op., at 10).
`
`
`
`Because the “standard evidentiary breath test is conducted
`after a motorist is arrested and transported to a police
`station” or another appropriate facility, ibid., the im-
`portant question here is what officers may do when a
`driver’s unconsciousness (or stupor) eliminates any rea-
`
`sonable opportunity for that kind of breath test.
`
`III
`
`
`The Fourth Amendment guards the “right of the people
`
`to be secure in their persons . . . against unreasonable
`searches” and provides that “no Warrants shall issue, but
`upon probable cause.” A blood draw is a search of the
`
`
`
`
`
`

`

`
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`
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`
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`8
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`MITCHELL v. WISCONSIN
`
`Opinion of ALITO, J.
`
` person, so we must determine if its administration here
`
`without a warrant was reasonable. See Birchfield, 579
`U. S. at ___ (slip op., at 14). Though we have held that a
`warrant is normally required, we have also “made it clear
`that there are exceptions to the warrant requirement.”
`
`Illinois v. McArthur, 531 U. S. 326, 330 (2001). And under
`the exception for exigent circumstances, a warrantless
`search is allowed when “‘there is compelling need for
`official action and no time to secure a warrant.’” McNeely,
`
`supra, at 149 (quoting Michigan v. Tyler, 436 U. S. 499,
`509 (1978)). In McNeely, we considered how the exigent-
`circumstances exception applies to the broad category of
`cases in which a police officer has probable cause to be-
`lieve that a motorist was driving under the influence of
`
`alcohol, and we do not revisit that question. Nor do we
`
`settle whether the exigent-circumstances exception covers
`the specific facts of this case.2 Instead, we address how
`——————
`
`
` 2 JUSTICE SOTOMAYOR’s dissent argues that Wisconsin waived the
`
` argument that we now adopt, but the dissent paints a misleading
`picture of both the proceedings below and the ground for our decision.
`
`
`First, as to the proceedings below, the dissent contends that the sole
`question certified to the Wisconsin Supreme Court was “ ‘whether the
`
`
`warrantless blood draw of an unconscious motorist pursuant to Wiscon-
`
`sin’s implied consent law, where no exigent circumstances exist or have
`
`been argued, violates the Fourth Amendment.’ ” Post, at 3 (quoting
`
`App. 61). That is indeed how the intermediate appellate court under-
`stood the issue in the case, but the State Supreme Court took a broader
`view, as was its right. It regarded the appeal as presenting two ques-
`
`tions, one of which was “whether a warrantless blood draw from an
`unconscious person pursuant to Wis. Stat. §343.305(3)(b) violates the
`
`Fourth Amendment.” See 383 Wis. 2d 192, 202–203, 914 N. W. 2d
`
`151,155–156 (2018). This broad question easily encompasses the
`
`rationale that we adopt today.
`
`
`
`Second, after noting that the State did not attempt below to make a
`
`case-specific showing of exigent circumstances, the dissent claims that
`
`
`
`our decision is based on this very ground. But that is not at all the
`
`basis for our decision. We do not hold that the State established that
`
`
`the facts of this particular case involve exigent circumstances under
`
`
`
`
`
`

`

`
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`9
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` Cite as: 588 U. S. ____ (2019)
`
`
`Opinion of ALITO, J.
`the exception bears on the category of cases encompassed
`
`by the question on which we granted certiorari—those
`involving unconscious drivers.3 In those cases, the need
`for a blood test is compelling, and an officer’s duty to
`attend to more pressing needs may leave no time to seek a
`warrant.
`
`
`A
`The importance of the needs served by BAC testing is
`
`hard to overstate. The bottom line is that BAC tests are
`
`needed for enforcing laws that save lives. The specifics, in
`
`short, are these: Highway safety is critical; it is served by
`
`laws that criminalize driving with a certain BAC level;
`
`
`——————
`McNeely. Rather, we adopt a rule for an entire category of cases—
`
`those in which a motorist believed to have driven under the influence of
`
`alcohol is unconscious and thus cannot be given a breath test. This rule
`is not based on what happened in petitioner’s particular case but on the
`
`circumstances generally present in cases that fall within the scope of
`
`the rule. Those are just the sorts of features of unconscious-driver
`
`cases that Wisconsin brought to our attention, see Brief for Respondent
`
`54–55; Tr. of Oral Arg. at 32–34, 48–51, which petitioner addressed, see
`
`Reply Brief at 14–15; Tr. of Oral Arg. at 15–20, 23–24, 29–31, 63–66.
`
`
`So it is entirely proper for us to decide the case on this ground. See
`
`Thigpen v. Roberts, 468 U. S. 27, 29–30 (1984).
`3While our exigent-circumstances precedent requires a “ ‘totality of
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`the circumstances’ ” analysis, “the circumstances in drunk driving cases
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`are often typical, and the Court should be able to offer guidance on how
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` police should handle cases like the one before us.” McNeely, 569 U. S.,
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`at 166 (ROBERTS, C. J., concurring in part and dissenting in part).
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`Indeed, our exigency case law is full of general rules providing such
`guidance. Thus, we allow police to proceed without a warrant when an
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`occupant of a home requires “emergency assistance,” Brigham City v.
`Stuart, 547 U. S. 398, 403 (2006); when a building is on fire,
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`see Michigan v. Tyler, 436 U. S. 499, 509 (1978); and when an armed
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`robber has just entered a home, see United States v. Santana, 427 U. S.
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`38 (1976). “In each of these cases, the requirement that we base our
`decision on the ‘totality of the circumstances’ has not prevented us from
`spelling out a general rule for the police to follow.” McNeely, supra, at
`168 (opinion of ROBERTS, C. J.). Neither does it prevent us here.
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` MITCHELL v. WISCONSIN
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`Opinion of ALITO, J.
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`and enforcing these legal BAC limits requires efficient
`testing to obtain BAC evidence, which naturally dissi-
`pates. So BAC tests are crucial links in a chain on which
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`vital interests hang. And when a breath test is unavail-
`able to advance those aims, a blood test becomes essential.
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`Here we add a word about each of these points.
`First, highway safety is a vital public interest. For
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`
`decades, we have strained our vocal chords to give ade-
`quate expression to the stakes. We have called highway
`safety a “compelling interest,” Mackey, 443 U. S., at 19; we
`have called it “paramount,” id., at 17. Twice we have
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`referred to the effects of irresponsible driving as “slaugh-
`ter” comparable to the ravages of war. Breithaupt v.
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`Abram, 352 U. S. 432, 439 (1957); Perez v. Campbell, 402
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`U. S. 637, 657, 672 (1971) (Blackmun, J., concurring in
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`result in part and dissenting in part). We have spoken of
`“carnage,” Neville, 459 U. S., at 558–559, and even “fright-
`ful carnage,” Tate v. Short, 401 U. S. 395, 401 (1971)
`(Blackmun, J., concurring). The frequency of preventable
`collisions, we have said, is “tragic,” Neville, supra, at 558,
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`and “astounding,” Breithaupt, supra, at 439. And behind
`this fervent language lie chilling figures, all captured in
`the fact that from 1982 to 2016, alcohol-related accidents
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`took roughly 10,000 to 20,000 lives in this Nation every
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`single year. See National Highway Traffic Safety Admin.
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`(NHTSA), Traffic Safety Facts 2016, p. 40 (May 2018). In
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`the best years, that would add up to more than one fatality
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`per hour.
`Second, when it comes to fighting these harms and
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`promoting highway safety, federal and state lawmakers
`have long been convinced that specified BAC limits make
`a big difference. States resorted to these limits when
`earlier laws that included no “statistical definition of
`intoxication” proved ineffectual or hard to enforce. See
`Birchfield, 579 U. S., at ___–___ (slip op., at 2–3). The
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`maximum permissible BAC, initially set at 0.15%, was
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`Cite as: 588 U. S. ____ (2019)
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`Opinion of ALITO, J.
`first lowered to 0.10% and then to 0.08%. Id., at ___, ___–
`___ (slip op., at 3, 6–7). Congress encouraged this process
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`by conditioning the award of federal highway funds on the
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`establishment of a BAC limit of 0.08%, see 23 U. S. C.
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`§163(a); 23 CFR §1225.1 (2012), and every State has
`adopted this limit.4 Not only that, many States, including
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`Wisconsin, have passed laws imposing increased penalties
`for recidivists or for drivers with a BAC level that exceeds
`a higher threshold. See Wis. Stat. §346.65(2)(am); Birch-
`field, 579 U. S., at ___ (slip op., at 7).
`
`There is good reason to think this strategy has worked.
`As we noted in Birchfield, these tougher measures corre-
`sponded with a dramatic drop in highway deaths and
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`injuries: From the mid-1970’s to the mid-1980’s, “the
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`number of annual fatalities averaged 25,000; by 2014 . . . ,
`the number had fallen to below 10,000.” Id., at ___ (slip
`op., at 6).
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`Third, enforcing BAC limits obviously requires a test
`that is accurate enough to stand up in court, id., at ___–
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`___ (slip op., at 3–5); see also McNeely, 569 U. S., at 159–
`160 (plurality opinion). And we have recognized that
`“[e]xtraction of blood samples for testing is a highly effec-
`
`tive means of ” measuring “the influence of alcohol.”
`Schmerber, 384 U. S., at 771.
`
`Enforcement of BAC limits also requires prompt testing
`because it is “a biological certainty” that “[a]lcohol dissi-
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`pates from the bloodstream at a rate of 0.01 percent to
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`0.025 percent per hour. . . . Evidence is literally disappear-
`ing by the minute.” McNeely, 569 U. S., at 169 (opinion of
`ROBERTS, C. J.). As noted, the ephemeral nature of BAC
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`was “essential to our holding in Schmerber,” which itself
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`Id., at 152
`allowed a warrantless blood test for BAC.
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`——————
`4See NHTSA, Alcohol and Highway Safety: A Review of the State of
`Knowledge 167 (DOT HS 811 374, Mar. 2011).
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` MITCHELL v. WISCONSIN
`
`Opinion of ALITO, J.
`
`(opinion of the Court). And even when we later held that
`the exigent-circumstances exception would not permit a
`warrantless blood draw in every drunk-driving case, we
`acknowledged that delays in BAC testing can “raise ques-
`tions about . . . accuracy.” Id., at 156.
`
`It is no wonder, then, that the implied-consent laws that
`incentivize prompt BAC testing have been with us for 65
`
`years and now exist in all 50 States. Birchfield, supra, at
`___ (slip op., at 6). These laws and the BAC tests they
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`require are tightly linked to a regulatory scheme that
`serves the most pressing of interests.
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`Finally, when a breath test is unavailable to promote
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`those
`interests, “a blood draw becomes necessary.”
`McNeely, 569 U. S., at 170 (opinion of ROBERTS, C. J.).
`
`Thus, in the case of unconscious drivers, who cannot blow
`into a breathalyzer, blood tests are essential for achieving
`the compelling interests described above.
`Indeed, not only is the link to pressing interests here
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`tighter; the interests themselves are greater: Drivers who
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`are drunk enough to pass out at the wheel or soon after-
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`ward pose a much greater risk. It would be perverse if the
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`more wanton behavior were rewarded—if the more har-
`rowing threat were harder to punish.
`For these reasons, there clearly is a “compelling need”
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`for a blood test of drunk-driving suspects whose condition
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`deprives officials of a reasonable opportunity to conduct a
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`breath test. Id., at 149 (opinion of the Court) (internal
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`quotation marks omitted). The only question left, under
`our exigency doctrine, is whether this compelling need
`justifies a warrantless search because there is, further-
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`more, “‘no time to secure a warrant.’” Ibid.
`B
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`We held that there was no time to secure a warrant
`in
`before a blood test of a drunk-driving suspect
`Schmerber because the officer there could “reasonably
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`Opinion of ALITO, J.
`have believed that he was confronted with an emergency,
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` in which the delay necessary to obtain a warrant, under
`the circumstances, threatened the destruction of evi-
`dence.” 384 U. S., at 770 (internal quotation marks omit-
`ted). So even if the constant dissipation of BAC evidence
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`alone does not create an exigency, see McNeely, supra, at
`150–151, Schmerber shows that it does so when combined
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`with other pressing needs:
`“