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Fourth Amendment

Mitchell v. Wisconsin


Drunk driving, as the Supreme Court has repeatedly, emphatically made clear, poses a significant threat to public safety.1×1. See, e.g., Birchfield v. North Dakota, 136 S. Ct. 2160, 2166 (2016) (“Drunk drivers take a grisly toll on the Nation’s roads, claiming thousands of lives, injuring many more victims, and inflicting billions of dollars in property damage every year.”). To punish those who do drive drunk and deter those who would, states have enacted laws that impose criminal penalties on drivers with blood alcohol content (BAC) over a set amount.2×2. See, e.g., Cal. Veh. Code § 23152(b) (West 2019) (prohibiting a person with a 0.08% BAC or over from driving a vehicle); N.C. Gen. Stat. § 20-138.1(a)(2) (2019) (same). In these cases, proof of the driver’s BAC is a crucial piece of evidence, but one that is continuously disappearing as the alcohol in the driver’s bloodstream dissipates. Officers who seek to enforce drunk driving laws therefore face a dilemma: though blood draws, which provide proof of BAC, are searches subject to the Fourth Amendment’s warrant requirement,3×3. See Schmerber v. California, 384 U.S. 757, 767 (1966). BAC evidence might vanish in the time it takes to secure a warrant. Last Term, in Mitchell v. Wisconsin,4×4. 139 S. Ct. 2525 (2019). the Court addressed this dilemma, holding that when a suspected drunk driver falls unconscious, requiring officers to take the driver to a hospital before administering a breath test, the officers may “almost always” order a warrantless blood test to measure BAC.5×5. Id. at 2539 (plurality opinion). In its focus on unconscious drunk drivers unable to perform breath tests, Mitchell seems quite narrow. But that narrowness is illusory. By embracing broad health and safety language and reconstructing past cases, its reasoning introduces a potentially broad expansion of the exigency exception to the warrant requirement. Mitchell thus serves as an example of the Court undermining Fourth Amendment protections even as it seems to issue limited, precedent-bound opinions.

On May 30, 2013, the City of Sheboygan Police Department received a 911 call reporting that petitioner Gerald Mitchell had entered a van and driven away while visibly intoxicated.6×6. State v. Mitchell, 914 N.W.2d 151, 154 (Wis. 2018). An officer later found Mitchell walking near a lake, stumbling and slurring his speech, with his van parked nearby.7×7. Mitchell, 139 S. Ct. at 2542 (Sotomayor, J., dissenting). The officer administered a preliminary breath test, which registered a BAC of 0.24%, and arrested Mitchell for operating a vehicle while intoxicated.8×8. Id. at 2532 (plurality opinion). En route to the station, Mitchell’s condition deteriorated.9×9. Id. Determining that an evidentiary breath test would not be possible, the officer drove Mitchell to a nearby hospital for a blood test.10×10. Mitchell, 914 N.W.2d at 155. By the time they arrived, Mitchell was fully unconscious, and the officer directed hospital staff to draw a blood sample.11×11. Mitchell, 139 S. Ct. at 2532 (plurality opinion). By this point, about ninety minutes had passed since Mitchell’s arrest, and the test revealed a BAC of 0.222%.12×12. Id. Prosecutors charged Mitchell with violating two Wisconsin drunk driving laws.13×13. Id.

Mitchell moved to suppress the blood test results, arguing that the warrantless blood draw constituted an unreasonable search under the Fourth Amendment.14×14. Id. Wisconsin responded that its implied-consent law establishes that unconscious drivers are presumed to have consented to blood draws.15×15. See Mitchell, 914 N.W.2d at 155. Under this law, drivers who operate vehicles on Wisconsin public highways are “deemed to have given consent” to blood, urine, and breath testing, and unconscious drivers “are presumed not to have withdrawn consent.” Wis. Stat. § 343.305 (2019). Accordingly, the state argued, Mitchell’s blood draw “pass[ed] constitutional muster.”16×16. State v. Mitchell, No. 2015AP304-CR, 2017 WL 9803322, at *4 (Wis. Ct. App. May 17, 2017). The trial court denied Mitchell’s motion to suppress, and a jury convicted him.17×17. Mitchell, 139 S. Ct. at 2532 (plurality opinion). The state court of appeals then certified the case to the Wisconsin Supreme Court,18×18. Mitchell, 2017 WL 9803322, at *1. which upheld the warrantless blood draw and affirmed Mitchell’s convictions.19×19. Mitchell, 914 N.W.2d at 167.

The U.S. Supreme Court vacated the judgment and remanded the case.20×20. Mitchell, 139 S. Ct. at 2539 (plurality opinion). Writing for the plurality, Justice Alito21×21. Justice Alito was joined by Chief Justice Roberts and Justices Breyer and Kavanaugh. situated the case within the Court’s Fourth Amendment jurisprudence on warrantless BAC tests.22×22. See Mitchell, 139 S. Ct. at 2532–34 (plurality opinion). Because blood draws are searches,23×23. Id. at 2533 (citing Birchfield v. North Dakota, 136 S. Ct. 2160, 2173 (2016)). officers can administer them only with a warrant or when an exception to the warrant requirement applies.24×24. Id. He noted that in prior cases, the Court has found that the exigency exception can justify warrantless blood draws, with the exigency at issue being the destruction of BAC evidence.25×25. Id. (citing Missouri v. McNeely, 569 U.S. 141, 152 (2013)). In Missouri v. McNeely,26×26. 569 U.S. 141. the Court concluded that “the fleeting quality of BAC evidence alone is not enough” to allow warrantless blood draws in all drunk driving cases.27×27. Mitchell, 139 S. Ct. at 2533 (plurality opinion) (citing McNeely, 569 U.S. at 156). However, Schmerber v. California28×28. 384 U.S. 757 (1966). suggests that circumstances that prevent the police from immediately seeking a warrant heighten the “degree of urgency” and can justify warrantless blood testing.29×29. Mitchell, 139 S. Ct. at 2533 (plurality opinion).

Justice Alito proceeded to lay out the general standard for the exigency exception. As he explained, “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.’”30×30. Id. at 2534 (quoting McNeely, 569 U.S. at 149). The question, then, was whether the exception applied to blood tests of unconscious drivers who appear to have driven under the influence of alcohol.31×31. Id. at 2534–35, 2535 n.2.

Addressing the first requirement, Justice Alito found the “importance of the needs served by BAC testing . . . hard to overstate.”32×32. Id. at 2535. But over the years the Court has made a good effort, “strain[ing its] vocal chords to give adequate expression”33×33. Id. to the importance of highway safety and to the “‘slaughter’ comparable to the ravages of war”34×34. Id. (quoting Perez v. Campbell, 402 U.S. 637, 657, 672 (1971) (Blackmun, J., concurring in result in part and dissenting in part); and quoting Breithaupt v. Abram, 352 U.S. 432, 439 (1957)). caused by irresponsible driving. The passage of laws punishing those who drive with BACs over set limits has correlated with a drop in highway deaths and injuries.35×35. Id. at 2536 (quoting Birchfield v. North Dakota, 136 S. Ct. 2160, 2169 (2016)). To enforce these laws, police must be able to accurately and promptly test the BAC of suspected drunk drivers, since alcohol dissipates in the bloodstream over time.36×36. Id. (quoting Missouri v. McNeely, 569 U.S. 141, 169 (2013) (Roberts, C.J., concurring in part and dissenting in part)). When evidentiary breath tests are unavailable, as in the case of unconscious drivers, blood draws become necessary.37×37. Id. at 2536–37 (quoting McNeely, 569 U.S. at 170 (Roberts, C.J., concurring in part and dissenting in part)). Thus, Justice Alito concluded, “there clearly is a ‘compelling need’” for blood tests of suspected drunk drivers unable to perform evidentiary breath tests.38×38. Id. at 2537 (quoting McNeely, 569 U.S. at 149).

He then turned to the second exigency requirement: that officers have no time to secure a warrant. Citing Schmerber and McNeely,39×39. See id. (quoting Schmerber v. California, 384 U.S. 757, 770–71 (1966)). he argued that “exigency exists when (1) BAC evidence is dissipating and (2) some other factor creates pressing health, safety, or law enforcement needs that would take priority over a warrant application.”40×40. Id. In Mitchell, that extra factor was the driver’s unconsciousness. Unconsciousness, Justice Alito pressed, creates an immediate medical emergency, and the time it might take to secure medical care could prevent officers from obtaining a warrant while BAC evidence is still present.41×41. Id. at 2537–38. Further, if an unconscious driver were to crash, officers might face the additional burdens of acting as first responders for those injured, preserving evidence at the scene, and redirecting traffic.42×42. Id. at 2538. Justice Alito acknowledged that technological developments have streamlined the process of obtaining a warrant, but maintained that “forcing police to put off other tasks [in favor of seeking a warrant] for even a relatively short period of time may have terrible collateral costs.”43×43. Id. at 2539.

The plurality concluded that the exigency exception “almost always” covers instances in which a suspected drunk driver’s “unconsciousness or stupor requires him to be taken to the hospital or similar facility before police have a reasonable opportunity to administer a standard evidentiary breath test.”44×44. Id. However, in “unusual case[s]” in which a driver can show that his blood “would not have been drawn if police had not been seeking BAC information, and that police could not have reasonably judged that a warrant application would interfere with other pressing needs or duties,” a warrantless blood draw of an unconscious driver might violate the Fourth Amendment.45×45. Id. Because Mitchell did not have a chance to make this showing, the Court remanded the case.46×46. Id.

Justice Thomas concurred in the judgment. Characterizing the plurality’s holding as burdensome to both officers and courts, he instead advocated for a per se rule, in which police would always be permitted to order warrantless blood testing of suspected drunk drivers.47×47. Id. (Thomas, J., concurring) (citing Birchfield v. North Dakota, 136 S. Ct. 2160, 2197–98 (2016) (Thomas, J., concurring in judgment in part and dissenting in part)). In drunk driving cases, he explained, the imminent destruction of evidence is always a risk, regardless of whether the additional factors that the plurality pointed to are present.48×48. Id. at 2540 (quoting Missouri v. McNeely, 569 U.S. 141, 178 (2013) (Thomas, J., dissenting)). Accordingly, he argued that once police have probable cause to believe a driver is drunk, “[t]he destruction of evidence alone is sufficient to justify a warrantless search based on exigent circumstances.”49×49. Id. (citing McNeely, 569 U.S. at 176–79 (Thomas, J., dissenting)). For an analysis of the tension between Fourth Amendment rules and standards underlying Mitchell, see Orin S. Kerr, Drunk Driving, Blood Draws, and the Fourth Amendment After Mitchell v. Wisconsin, Volokh Conspiracy (July 1, 2019, 11:23 PM), https://reason.com/2019/07/01/drunk-driving-blood-draws-and-the-fourth-amendment-after-mitchell-v-wisconsin [https://perma.cc/68MB-CAYU].

Justice Sotomayor dissented.50×50. Justice Sotomayor was joined by Justices Ginsburg and Kagan. Like Justice Alito, she sought to situate Mitchell within established precedent on warrantless blood tests.51×51. See Mitchell, 139 S. Ct. at 2543–44, 2547 (Sotomayor, J., dissenting). Across these cases, she noted, the Court has maintained “that there is no categorical exigency exception for blood draws.”52×52. Id. at 2544. Rather, lower courts must determine in each case whether officers have actually faced circumstances that would have prevented a timely warrant application.53×53. Id. at 2547.[I]f the police have time to secure a warrant before the blood draw, ‘the Fourth Amendment mandates that they do so.’”54×54. Id. (quoting McNeely, 569 U.S. at 152).

Justice Sotomayor pointed to specific factors suggesting that, in many drunk driving cases, officers do have time to secure a warrant. First, when officers suspect someone of driving drunk, they typically must transport her to a medical facility in order to gather BAC evidence — in this “built-in delay,” there may be time to seek a warrant.55×55. Id. at 2548. Further, alcohol dissipates in the bloodstream gradually and predictably, meaning that BAC tests done some time after an initial arrest can still provide reliable evidence of what the driver’s BAC was.56×56. Id. Finally, new technology has allowed officers to obtain warrants faster and more easily than ever before.57×57. Id. These factors apply with equal force when a driver is unconscious.58×58. Id. at 2548–49.

The dissent rejected the plurality’s contention that because unconscious drivers invariably need medical attention, the exigency exception will almost always apply in this context. Justice Sotomayor disagreed that a driver’s unconsciousness poses a unique crisis for police officers.59×59. Id. at 2549–50. As she pointed out, most drunk drivers need medical attention,60×60. Id. at 2549 (quoting Missouri v. McNeely, 569 U.S. 141, 171 (2013) (Roberts, C.J., concurring in part and dissenting in part)). but the Court has refused to extend the exigency exception to all drunk driving cases.61×61. Id. Moreover, the necessity of a medical response, she emphasized, does not always interfere with officers’ ability to get a warrant.62×62. Id. (first citing McNeely, 569 U.S. at 153–54; and then citing id. at 171–72 (Roberts, C.J., concurring in part and dissenting in part)). Though officers may in some instances be “truly confronted with a ‘now or never’ situation,”63×63. Id. at 2550 (quoting McNeely, 569 U.S. at 153). she argued that courts should decide each case on its own facts and avoid the kind of “de facto categorical exigency exception” advocated by the plurality.64×64. Id. Justice Sotomayor also addressed and rejected the State’s implied-consent argument, concluding that a statute “cannot itself create the actual and informed consent that the Fourth Amendment requires.” Id. at 2545. She criticized the plurality for instead focusing on the exigency exception, as the State waived its exigency argument. Id. at 2545–46. Justice Alito disagreed that the issue was waived. As the Wisconsin Supreme Court addressed whether a warrantless blood draw from an unconscious person pursuant to Wisconsin’s presumed consent statute violated the Fourth Amendment, “[t]his broad question easily encompass[ed]” the plurality’s approach. Id. at 2534 n.2 (plurality opinion).

Justice Gorsuch also dissented. In his view, the Court granted certiorari to decide whether Wisconsin’s implied-consent statute means that “Wisconsin drivers impliedly consent to blood alcohol tests.”65×65. Id. at 2551 (Gorsuch, J., dissenting). Because the Court decided the case under the exigency doctrine, which “neither the parties nor the courts below discussed,” he would have dismissed the case as “improvidently granted.”66×66. Id.

At first glance, Mitchell seems like a narrow opinion,67×67. See Kerr, supra note 49 (referring to the plurality decision as “relatively narrow”). and it is not difficult to see why. By basing its holding on the exigency exception, the Court declined to give constitutional recognition to Wisconsin’s theory of implied consent — a theory that could significantly expand the Fourth Amendment’s consent exception,68×68. The question of whether someone has given legally valid consent to a search is one “of fact to be determined from the totality of all the circumstances.” Schneckloth v. Bustamonte, 412 U.S. 218, 227 (1973). Had the Court endorsed the theory of implied consent, it would have eliminated the requirement of a contextual inquiry and suggested that consent can be presumed solely by one’s choice to participate in a given activity — here, driving. See Brief for the Petitioner at 29–30, Mitchell, 139 S. Ct. 2525 (No. 18-6210); see also Kerr, supra note 49 (describing the implied-consent theory as “an easy way to eliminate Fourth Amendment rights”). but that the Court seems reluctant to fully endorse.69×69. The Court’s avoidance of the implied-consent arguments was unusual, as nearly every brief focused on that issue. See, e.g., Brief of the Respondent, State of Wisconsin, Mitchell, 139 S. Ct. 2525 (No. 18-6210). That it decided the case on completely different grounds might signal that the Court is unwilling to validate the theory of implied consent. Instead, the plurality drew on established precedent and put forward a rule limited to cases just like Mitchell’s, in which police have probable cause to believe that a driver is drunk, and the driver is unconscious, unable to complete a breath test, and heading to a medical facility anyway. But Mitchell also contains broader reasoning establishing the exigency exception’s role in blood-testing cases in general. Its articulation of the exception departs from the Court’s precedent in the area and threatens to justify warrantless blood draws in a much larger class of cases, both within and beyond the context of drunk driving. Mitchell, then, appears to be an example of the Court’s subtle weakening of Fourth Amendment protections through unannounced expansions of existing exceptions.

Particularly given the jurisprudential road not taken, Mitchell’s holding seems quite limited. Justice Alito announced as much, claiming that the Court was addressing a “narrow but important category of cases: those in which [a driver who seems to be under the influence of alcohol] is unconscious and therefore cannot be given a breath test.”70×70. Mitchell, 139 S. Ct. at 2531 (plurality opinion). In line with this framing, his holding purports to apply only to cases in which a number of specific factors are present — those in which: (1) police have probable cause that someone has committed a drunk driving offense; (2) the driver’s unconsciousness requires that he be taken to a medical facility before police can administer an evidentiary breath test; (3) the driver’s blood will be drawn anyway; and (4) police reasonably judge that a warrant application will interfere with other pressing needs.71×71. See id. at 2539; see also Kerr, supra note 49 (unpacking this rule). In addition to depicting the decision’s impact as small, Justice Alito framed it as a small step from existing doctrine: Schmerber and McNeely, he explained, create a “spectrum” of exigent circumstances and essentially decide Mitchell, whose facts position it closer to Schmerber, in which a warrantless blood draw was justified, than McNeely, in which it was not.72×72. Mitchell, 139 S. Ct. at 2533 (plurality opinion); see also id. at 2537–38.

However, within this apparently narrow holding is much broader language on when the exigency exception applies in all blood-test cases. In his discussion of the role of the exigency exception in drunk driving cases in general, Justice Alito set out a rule, which ostensibly comes from his analysis of Schmerber: “Thus, exigency exists when (1) BAC evidence is dissipating and (2) some other factor creates pressing health, safety, or law enforcement needs that would take priority over a warrant application.”73×73. Id. at 2537. In other words, in almost every case with potential BAC evidence,74×74. Since BAC evidence is always dissipating, prong one of this rule will always be satisfied when a suspect is intoxicated. police are entitled to order a warrantless blood draw so long as they can demonstrate the existence of some health, safety, or law enforcement need when they encounter a suspect.75×75. Mitchell does impose some limitations on officers. Even if a health, safety, or law enforcement need is present, a defendant still might suppress BAC evidence if she can show both that her blood would not have been drawn had police not been seeking BAC information and that police could not have reasonably judged that a warrant application would have interfered with other pressing needs. Mitchell, 139 S. Ct. at 2539 (plurality opinion). However, the plurality notes that such cases will be “unusual” and puts the burden on the defendant to establish these factors. Id. Further, this concession comes when Justice Alito states the narrow holding about unconscious drivers, distancing it rhetorically (and perhaps legally) from his articulation of the exigency rule. These features suggest that the carveout that Mitchell offers will rarely apply, especially when considering the judicial instinct to defer to police on the reasonableness of in-the-moment decisionmaking. See David A. Sklansky, Traffic Stops, Minority Motorists, and the Future of the Fourth Amendment, 1997 Sup. Ct. Rev. 271, 301 (“Far more often than not, federal judges find the inferences drawn and actions taken by law enforcement officers reasonable, and deny suppression motions challenging those inferences and actions.”). What exactly constitutes a health, safety, or law enforcement need is left vague — and potentially expansive.76×76. Cf. William J. Stuntz, Implicit Bargains, Government Power, and the Fourth Amendment, 44 Stan. L. Rev. 553, 554 (1992) (arguing that “special needs” is a vague term that “turns out to be no more than a label that indicates when a lax standard will apply”).

Nestled in the middle of the opinion, this declaration of the Court’s approach to BAC evidence marks a subtle but significant shift from previous cases. As the plurality explained, the Court’s two previous cases on when the exigency exception can justify a warrantless blood draw are Schmerber and McNeely. In Schmerber, the Court focused on that case’s particular facts and the amount of “time [that] had to be taken” by the officer in pursuit of his other responsibilities.77×77. Schmerber v. California, 384 U.S. 757, 770–71 (1966) (emphasis added). Mitchell, which purports to rely on Schmerber in its articulation of the exigency test, departs from it by holding that the mere existence of other factors competing for an officer’s attention can justify a warrantless search. McNeely reaffirmed Schmerber’s fact-specific inquiry, holding that “[i]n those drunk driving investigations where police officers can reasonably obtain a warrant before a blood sample can be drawn . . . the Fourth Amendment mandates that they do so.”78×78. Missouri v. McNeely, 569 U.S. 141, 152 (2013). The Court maintained that lower courts must inquire whether “in [a] particular case . . . a warrant could not have been obtained within a reasonable amount of time.”79×79. Id. at 163 (emphasis added); see also id. at 152–56. This focus on whether there are specific factors that prevent an officer from getting a warrant in time is a far cry from Mitchell’s emphasis on whether there are any health, safety, or law enforcement needs that might take priority over a warrant application. Where McNeely mandates an inquiry into whether a timely warrant application is actually possible, Mitchell requires just that there be some other demand on the officers’ attention to justify a warrantless blood draw. Mitchell therefore subtly but meaningfully expands the rule for when the state can invoke the exigency exception to justify a warrantless blood test.80×80. A number of states have already cited Mitchell’s broader language, rather than that of Schmerber or McNeely, in their definitions of when the exigency exception applies in blood-draw cases — including in cases where the driver was not unconscious. See, e.g., Answer Brief of Appellee at 19–20, Burrell v. Florida, No. 2D18-1108 (Fla. Dist. Ct. App. July 25, 2019); Reply Brief of Plaintiff-Appellant at 2–3, State v. Hay, No. 2018AP2240-CR (Wis. Ct. App. July 12, 2019).

Mitchell’s broadening of the exigency test means that officers will likely have an easier time justifying warrantless blood draws of all intoxicated drivers. Though Mitchell’s holding is limited to unconscious drivers, and though McNeely’s rejection of a per se rule for drunk driving remains, the plurality’s language effectively opens the door that McNeely purports to shut, allowing warrantless blood draws of almost any drunk driver. In many instances, an officer encountering a suspected drunk driver might conclude that the driver has pressing health needs, either because the driver is injured or because the driver’s apparent intoxication itself requires treatment.81×81. If, for example, a driver exhibits signs of alcohol poisoning, including “[c]onfusion,” experts recommend immediate medical treatment. Alcohol Poisoning, Mayo Clinic (Jan. 19, 2018), https://www.mayoclinic.org/diseases-conditions/alcohol-poisoning/symptoms-causes/syc-20354386 [https://perma.cc/Z5KB-GWZC]. Chief Justice Roberts has also noted that, in general, “[d]runk drivers often end up in an emergency room,” McNeely, 569 U.S. at 171 (Roberts, C.J., concurring in part and dissenting in part), suggesting that many drunk drivers have some health needs. Otherwise, the officer could easily find that there are safety or law enforcement needs present, such as diverting traffic, conducting a field sobriety test, searching the driver’s car, interviewing witnesses, or attending to anyone harmed by the driver.82×82. Indeed, in one vehicular manslaughter case in Texas, the court found that there were so many “important law enforcement [and] public-safety duties” that fourteen officers were too busy to secure a warrant. Cole v. State, 490 S.W.3d 918, 926 (Tex. Crim. App. 2016). Though these routine tasks might not prevent officers from filing a timely warrant application, as McNeely would require, they could very well “take priority over a warrant application” under Mitchell. So long as an officer “reasonably judge[s]”83×83. Mitchell, 139 S. Ct. at 2539 (plurality opinion). — or, more cynically, is willing to testify84×84. The practice of police committing perjury in order to support a warrantless search after the fact is well-documented and persistent. See Morgan Cloud, Essay, The Dirty Little Secret, 43 Emory L.J. 1311, 1311–21 (1994). But even beyond intentional lies, officers sometimes deploy “scripts,” in which they emphasize certain facts or narratives that they know will establish probable cause or reasonable suspicion. See Jeffrey Fagan & Amanda Geller, Following the Script: Narratives of Suspicion in Terry Stops in Street Policing, 82 U. Chi. L. Rev. 51, 55 (2015). It is not difficult to imagine such scripts for drunk driving stops. — that a health, safety, or law enforcement need was present and took priority over a warrant application, that officer will be entitled to order a blood draw of a suspect without a warrant. Thus, Mitchell may swallow the McNeely rule it claims to follow, creating a “presumption of exigent circumstances,”85×85. Mitchell, 139 S. Ct. at 2541 (Sotomayor, J., dissenting). as Justice Sotomayor put it, and providing justification for warrantless blood draws in a much larger category of cases than those involving unconscious defendants.86×86. Mitchell could also provide justification for warrantless blood draws in cases where someone is suspected of driving under the influence of drugs, which also present a continuous risk that evidence is being destroyed through the suspect’s metabolic processes. Indeed, the one brief in Mitchell that focused on the exigency exception contained an entire section discussing the importance of timely blood draws in cases with drug-impaired drivers. See Brief of Amici Curiae League of Wis. Municipalities, Wis. Towns Ass’n, and City of Eau Claire in Support of Respondent at 12–19, Mitchell, 139 S. Ct. 2525 (No. 18-6210). Lower courts have already applied McNeely in this context, see, e.g., Cole, 490 S.W.3d at 921, 923–27; City of Seattle v. Pearson, 369 P.3d 194, 199–201 (Wash. Ct. App. 2016), and Mitchell will likely play a role in future cases with drivers who are under the influence of drugs, which present similar, if not elevated, potential health, safety, and law enforcement needs.
At its most extreme, Mitchell might even extend to warrantless blood draws in drug-use and drug-possession cases where the police believe that a suspect’s blood contains drug evidence. In a number of jurisdictions, evidence of drugs in one’s bloodstream can provide circumstantial proof of prior drug use or possession. See, e.g., State v. Vorm, 570 N.E.2d 109, 110 (Ind. Ct. App. 1991); State v. Flinchpaugh, 659 P.2d 208, 212 (Kan. 1983); In re R.L.H., 116 P.3d 791, 795–96 (Mont. 2005); see also United States v. Blackston, 940 F.2d 877, 891 (3d Cir. 1991) (holding that urine sample testing positive for cocaine could be used as circumstantial evidence in a drug-possession case). If officers believe a suspect’s blood contains evidence of illegal drug use, the exigency exception could justify a warrantless blood draw — and at least one court has already applied McNeely to uphold evidence from a blood draw in these conditions. See State v. Parisi, 875 N.W.2d 619, 624, 628–30 (Wis. 2016).

In this quiet curtailment of established Fourth Amendment protections, Mitchell finds company in other recent Supreme Court cases. The Mitchell plurality purported to rely on precedent on warrantless blood draws, simply positioning its holding along an already-existing “spectrum.” But its reasoning has the effect of expanding the exigency exception in this area, in ways broader and more expansive than may initially be evident. Mitchell therefore fits into a trend of the Court weakening protections for criminal defendants by subtly but meaningfully expanding the scope of its established exceptions. In cases involving the reliability of anonymous tips,87×87. See Navarette v. California, 572 U.S. 393, 397–401 (2014) (citing precedent on the role of anonymous tips in reasonable suspicion determinations, but relying on different qualities of the tip at issue to come to the new conclusion that an anonymous tip alone, with few corroborated facts, “can demonstrate ‘sufficient indicia of reliability to [authorize an] investigatory stop,’” id. at 397 (quoting Alabama v. White, 496 U.S. 325, 327 (1990))); see also The Supreme Court, 2013 TermLeading Cases, 128 Harv. L. Rev. 191, 237–40 (2014) (explaining how the Court “sought guidance” from previous cases on anonymous tips, but “focused on facts not attended to in its existing . . . jurisprudence,” id. at 237, with the result being an “unwarranted curtailment of Fourth Amendment protections,” id. at 240). the good faith exception to the warrant requirement,88×88. See Herring v. United States, 555 U.S. 135, 137–38, 140–48 (2009) (applying the logic of the Court’s precedent on the good faith exception to the warrant requirement, but allowing for the first time that police personnel themselves be the source of the warrant deficiency); see also Jennifer E. Laurin, Essay, Trawling for Herring: Lessons in Doctrinal Borrowing and Convergence, 111 Colum. L. Rev. 670, 677, 679–88 (2011) (highlighting “three aspects of [Herring] that depart from the precedents to which the Court claim[ed] deference,” id. at 677). and the elements of reasonable suspicion,89×89. See Illinois v. Wardlow, 528 U.S. 119, 124 (2000) (relying on Terry v. Ohio, 392 U.S. 1 (1968), to support the contention that an officer can stop someone based on “reasonable suspicion,” and allowing that the person’s presence in a “high crime area” can be a determining factor supporting that suspicion). Though framed as a simple application of Terry’s contextual approach to reasonable suspicion, Wardlow has made the fact that a stop occurred in a high-crime area “dispositive” in many cases, Andrew Manuel Crespo, Systemic Facts: Toward Institutional Awareness in Criminal Courts, 129 Harv. L. Rev. 2050, 2078 (2016), and has opened the door to stops justified in large part by unchallenged assertions that the area in which they occurred was high crime, see id. & n.125. the Court did not announce a dramatic departure from precedent and, indeed, claimed to be simply applying rules from previous cases. But on its way to each holding, it recharacterized or extended the limits of these prior cases, weakening their protective force. Mitchell follows a similar path, providing another example of the Court quietly limiting the scope of existing Fourth Amendment doctrine.90×90. Another moment of quietly but significantly expansive reasoning in Mitchell comes when Justice Alito suggests that the fact that a driver’s blood will be drawn for medical reasons anyway means that a blood draw ordered by the police is less of an intrusion. See Mitchell, 139 S. Ct. at 2538 & n.8 (plurality opinion). This consideration of the relative intrusiveness of different blood draws seems to challenge Schmerber’s clear holding that police-ordered blood draws are searches — no matter what other medical procedures might take place around them. See id. at 2549–50, 2549 n.6 (Sotomayor, J., dissenting).

After Mitchell, all people suspected of driving drunk, as well as those who have not entered cars at all, are left more vulnerable to the possibility that police, without a warrant, might collect sensitive, personal information about them through blood draws.91×91. See Birchfield v. North Dakota, 136 S. Ct. 2160, 2178 (2016) (explaining that a blood test “places in the hands of law enforcement authorities a sample that can be preserved and from which it is possible to extract information beyond a simple BAC reading”). Perhaps this outcome is preferable to one entering new Fourth Amendment territory by validating implied-consent laws. But by both applying and expanding the exigency exception in one breath, the Mitchell plurality may have done lasting damage to constitutional protections that criminal defendants have already fought for and won.