¶ 1. The State appeals from a *187published court of appeals decision, State v. Faust, 2003 WI App 243, 267 Wis. 2d 783, 672 N.W.2d 97, which affirmed an order of the Sheboygan County Circuit Court, Gary J. Langhoff, Judge, granting the defendant's motion to suppress the results of a forced blood draw taken from him that indicated he was operating a motor vehicle with a prohibited alcohol concentration.
I. ISSUE
¶ 2. The issue presented is whether, under the Fourth Amendment to the United States Constitution and Article I, Section 11 of the Wisconsin Constitution, exigent circumstances exist for a nonconsensual war-rantless blood draw after the police have obtained what the arresting officer believes to be a voluntary, satisfactory, and useable chemical breath test indicating that the individual arrested was operating a motor vehicle with a prohibited level of alcohol concentration.1
¶ 3. For the reasons discussed below, we reaffirm that the rapid dissipation of alcohol in the bloodstream of an individual arrested for a drunk driving related offense constitutes an exigency that justifies the war-rantless nonconsensual test of that individual's blood, so long as the test satisfies the four factors enumerated in State v. Bohling, 173 Wis. 2d 529, 533-34, 494 N.W.2d 399 (1993). We hold that the presence of one presumptively valid chemical sample of the defendant's breath does not extinguish the exigent circumstances justifying a warrantless blood draw. The nature of the evidence sought — that is, the rapid dissipation of alcohol *188from the bloodstream — not the existence of other evidence, determines the exigency. Because exigent circumstances were present in this case and the blood test satisfied the test we set forth in Bohling, we reverse the decision of the court of appeals.
II. FACTUAL BACKGROUND
¶ 4. The operative facts of this case are undisputed. On February 19, 2002, Officer James Olsen of the Sheboygan Police Department was on routine patrol and was inspecting the license plates of vehicles parked behind a local tavern. Upon checking the plates of a 1998 Chevrolet coupe, Officer Olsen discovered that the plates were registered to an Audi coupe. A short time thereafter, Officer Olsen observed the vehicle leave the parking lot. Officer Olsen initiated a routine traffic stop, and the driver of the vehicle, the defendant, identified himself as one Jacob J. Faust. Officer Olsen noticed a "strong odor of intoxicants" emanating from the vehicle and observed that Faust was slurring his speech and exhibited bloodshot, glassy eyes. Upon questioning, Faust indicated to Officer Olsen that he had consumed "five brandies" before driving.
¶ 5. Officer Olsen thereafter administered a field sobriety test that Faust failed to successfully complete. Faust then voluntarily submitted to a preliminary breath test under Wis. Stat. § 343.303 (2001-02),2 the result of which indicated Faust possessed an alcohol *189concentration of 0.13.3 Officer Olsen placed Faust under arrest and transported him to police headquarters. Upon arriving, Faust consented to provide a sample of his breath for chemical analysis. The results of the breathalyzer indicated that Faust possessed an alcohol concentration of 0.09 grams of alcohol per 210 liters of breath. Officer Olsen then performed a search of Faust's criminal driving record, the result of which indicated that Faust had two prior convictions for operating a motor vehicle while intoxicated. As an individual with two or more prior convictions for operating a motorized vehicle while intoxicated, Faust was subject to the prohibited alcohol concentration of 0.08. Wis. Stat. § 885.235(lg)(cd).
¶ 6. Officer Olsen then requested that Faust provide a blood sample. After Officer Olsen read Faust the Informing the Accused form,4 Faust refused to submit to the blood test without giving any reason. Officer Olsen then issued a Notice of Intent to Revoke Faust's license for refusing the blood test.5 Faust was transported to the hospital where, following routine procedures, a phlebotomist administered the blood test. The result from the blood test indicated that Faust possessed a blood alcohol concentration of 0.1 grams of alcohol per 100 milliliters of blood. Officer Olsen did not *190request a drug analysis of Faust's blood sample. It is undisputed that Officer Olsen at no time sought a warrant for the blood test.
III. PROCEDURAL POSTURE
¶ 7. On March 7, 2002, the State filed a criminal complaint against Faust, alleging violations of Wis. Stat. § 346.63(l)(a) (operating while intoxicated) and Wis. Stat. § 346.63(l)(b) (operating with a prohibited alcohol concentration). On October 15, 2002, Faust filed a motion to suppress the results of the blood test, arguing that the warrantless test was taken in violation of the United States and Wisconsin Constitutions because exigent circumstances did not exist due to the fact that the arresting officer already had obtained what he believed to be a voluntary and sufficient breath test that indicated Faust's level of intoxication was in excess of the legal limit. At the motion hearing, Officer Olsen indicated that while it was not department procedure to request a blood test in all drunken driving cases, he sought a blood test for the purpose of gathering additional evidence because the previous two tests were very near the legal limit. Officer Olsen also testified that at the time the breathalyzer was administered, he believed it to be a voluntary and satisfactory test. The circuit court granted Faust's motion to suppress on February 25, 2003, concluding that "exigent circumstances did not exist to justify the warrantless taking of the Defendants blood."
¶ 8. The court of appeals, based on our decision in State v. Krajewski, 2002 WI 97, 255 Wis. 2d 98, 648 N.W.2d 385, affirmed the order of the circuit court. Faust, 267 Wis. 2d 783, ¶ 1. In Krajewski, this court held:
*191a warrantless nonconsensual blood draw from a person arrested on probable cause for a drunk driving offense is constitutional based on the exigent circumstances exception to the warrant requirement of the Fourth Amendment, even if the person offers to submit to a chemical test other than the blood test chosen by law enforcement, provided that the blood draw complies with the factors enumerated in Bohling.
Krajewski, 255 Wis. 2d 98, ¶ 3. However, we also stated in Krajewski that "[t]he exigency that exists because of dissipating alcohol does not disappear until a satisfactory, useable chemical test has been taken." Id., ¶ 40. The court of appeals concluded that this sentence from Krajewski compelled the conclusion that "once an individual arrested on probable cause for OWI has provided a satisfactory and useable chemical test, the exigent circumstances justifying a warrantless and nonconsen-sual blood draw no longer exist." Faust, 267 Wis. 2d 783, ¶ 1. In a concurring opinion, Judge Neal E Nettesheim stated that although he felt bound by this sentence from Krajewski, the remainder of the analysis in Kra-jewski contradicted this isolated passage. Faust, 267 Wis. 2d 783, ¶¶ 18-21 (Nettesheim, J. concurring).
IV STANDARD OF REVIEW
¶ 9. There are no genuine issues of material fact for the purposes of this appeal. Whether a nonconsen-sual warrantless blood draw taken to obtain evidence of a driver's blood alcohol concentration following an arrest falls within the exigent circumstances exception to the warrant requirement of the state and federal constitutions is a question of law that this court reviews de novo. Krajewski, 255 Wis. 2d 98, ¶ 17.
*192V ANALYSIS
A. Exigent Circumstances
¶ 10. We begin our analysis by reiterating some basic constitutional principles applicable to the case at bar. Both Article I, Section 11 of the Wisconsin Constitution and the Fourth Amendment of the United States Constitution "guarantee citizens the right to be free from" 'unreasonable searches.'" Bohling, 173 Wis. 2d at 536.6 A "compelled intrusion[ ] into the body for blood to be analyzed for alcohol content" constitutes a search under the Fourth Amendment. Schmerber v. California, 384 U.S. 757, 767-68 (1966).
¶ 11. Subject to a few well-delineated exceptions, warrantless searches are deemed per se unreasonable under the Fourth Amendment. Bohling, 173 Wis. 2d at 536 (quoting State v. Murdock, 155 Wis. 2d 217, 227, 455 N.W.2d 618 (1990)). It is clear that "[a] governmental search based on 'exigent circumstances,' like a search incident to an arrest, is a well-established exception to the warrant requirement." Id. at 537. Exigent circumstances are present so as to justify a search in the absence of a warrant where there is a threat that "evidence will be lost or destroyed if time is taken to obtain a warrant." Id. at 537-38.
*193¶ 12. The test for whether exigent circumstances are present is an objective one, id. at 538, and inquires into whether the officer "might reasonably have believed that he was confronted with an emergency, in which the delay necessary to obtain a warrant, under the circumstances, threatened 'the destruction of evidence[.]'" Schmerber, 384 U.S. at 770 (quoting Preston v. United States, 376 U.S. 364, 367 (1964)). In Schmerber, the United States Supreme Court established that the rapid metabolization and dissipation of alcohol from the bloodstream of an individual arrested for a drunk driving related offense qualifies as an exigent circumstance justifying the attempt to secure evidence of intoxication without first securing a warrant. Id. at 770-71.
¶ 13. Faust asks us to conclude that once the police have obtained what they believe at the time to be a voluntary, satisfactory, and useable chemical sample of the level of the defendant's intoxication, the exigency supporting a warrantless blood draw disappears. Faust's argument relies primarily upon one sentence from our decision in Krajewski, where we stated that "[t]he exigency that exists because of dissipating alcohol does not disappear until a satisfactory, useable chemical test has been taken." Krajewski, 255 Wis. 2d 98, ¶ 40.
¶ 14. In contrast, the State argues that the exigent circumstances exception to the warrant requirement of the Fourth Amendment is premised on the danger that evidence will be destroyed rather than whether the police already possess evidence of a criminal violation. The State contends that simply because the police already have collected what they believe to be a valid chemical sample establishing the defendant's level of intoxication does not remove the exigency. In *194other words, the State asserts that the circumstances giving rise to the exigency in the first instance — the rapid dissipation of alcohol from the bloodstream — are still present, regardless of whether the police have other evidence of intoxication.
¶ 15. We agree with the State and Judge Nettesheim's concurrence that to read the isolated passage from Krajewski upon which Faust relies as providing that exigent circumstances cease to exist in all cases when the police have already obtained a supposedly valid chemical test would he inconsistent with the nature of the exigency as illustrated in Bohling and Krajewski.
¶ 16. In Bohling, this court explained that Schmerber could be interpreted in one of two ways:
(a) that the rapid dissipation of alcohol in the bloodstream alone constitutes a sufficient exigency for a warrantless blood draw to obtain evidence of intoxication following a lawful arrest for a drunk driving related violation or crime — as opposed to taking a blood sample for other reasons, such as to determine blood type; or (b) that the rapid dissipation of alcohol in the bloodstream, coupled with an accident, hospitalization, and the lapse of two hours until arrest, constitute exigent circumstances for such a blood draw.
Bohling, 173 Wis. 2d at 539. We determined that the more reasonable interpretation of Schmerber was the former one: that exigent circumstances exist "based solely on the fact that alcohol rapidly dissipates in the bloodstream." Id. at 539.7 In other words, we deter*195mined in Bohling that Schmerber stands for the proposition that the fact that alcohol rapidly dissipates in the bloodstream justifies an officer's belief that he is faced with "an emergency, in which the delay necessary to obtain a warrant, under the circumstances, threatenfs] 'the destruction of evidence[.]'" Schmerber, 384 U.S. at 770 (citation omitted).
¶ 17. In addition, we noted that the United States Supreme Court has recognized that "in the context of a warrantless blood draw,... the Fourth Amendment warrant requirement is relaxed when the activity at issue constitutes a serious risk to public safety. Because of the public safety risk, persons engaging in such activities have a reduced expectation of privacy." Bohling, 173 Wis. 2d at 540 (citing Skinner v. Ry. Labor Executives Ass'n, 489 U.S. 602, 627 (1989)). We went on to explain the serious public safety concerns involved when a driver chooses to drive under the influence and that such concerns reduce a driver's expectation of privacy. Id. at 541.8 We explained that our interpretation of Schmerber "strikes a favorable balance between an individual's right to be free from unreasonable searches and Wisconsin's interest in enforcing its drunk *196driving laws. Wisconsin's interest is vital whereas the resulting intrusion on individual privacy is minimal." Id. at 545.
¶ 18. Therefore, we concluded that exigent circumstances exist based solely on the rapid dissipation of alcohol from a person's bloodstream, such that a war-rantless blood sample could lawfully be taken under the following circumstances:
(1) the blood draw is taken to obtain evidence of intoxication from a person lawfully arrested for a drunk-driving related violation or crime, (2) there is a clear indication that the blood draw will produce evidence of intoxication, (3) the method used to take the blood sample is a reasonable one and performed in a reasonable manner, and (4) the arrestee presents no reasonable objection to the blood draw.
Bohling, 173 Wis. 2d at 533-34.
¶ 19. In Krajewski, we determined that the exigency justifying a warrantless blood draw — the fact that evidence is likely to be destroyed — does not disappear "as soon as a person agrees to submit to a breath test as opposed to a blood test." Krajewski, 255 Wis. 2d 98, ¶ 36. Focusing on the destructibility of the evidence, we reasoned that "ftjhe exigency upon which a warrantless blood draw is premised is the dissipation of alcohol in the blood stream. An arrested person's offer to submit to one chemical test rather than another does not slow this dissipation. The evidence remains on a course to be destroyed." Id., ¶ 37 (emphasis added) (citations omitted).
¶ 20. Further, we noted that "[ejven when a person submits to a breath test in lieu of a blood test — outside the provisions of the implied consent statute — the test may be subject to challenge on grounds that the *197person's consent to the test was not given freely and voluntarily." Id., ¶ 41 (emphasis added). Ultimately, we reaffirmed the four-factor test set forth in Bohling and held that "a person's agreement to submit to a test of the person's choice does not negate the exigency, nor render unconstitutional a nonconsensual test of the officer's choice." Id. ¶ 63. We concluded:
[T]he rapid dissipation of alcohol in the bloodstream creates an exigency that justifies a nonconsensual test of the blood, breath, or urine of a person arrested for driving while intoxicated or other similar drunk-driving related offenses, so long as the test is administered pursuant to the factors enumerated in Bohling.
Id. (emphasis added).
¶ 21. The trouble with Faust's argument and both dissents is that they ignore the nature of the exigency that justifies a warrantless blood draw as described in Bohling and Krajewski. This court in Bohling and Krajewski clearly stated that the exigency justifying a warrantless blood draw is the rapid metabolization and dissipation of alcohol from the bloodstream. The reasoning of Krajewski — which focused on the rapid dissipation of alcohol from the blood stream — is inconsistent with the conclusion that the exigency disappears as soon as the police have obtained what they at the time believe to be a valid chemical breath sample.
¶ 22. The fact that the police have obtained a presumably valid chemical sample of the defendant's breath indicating the defendant's level of intoxication does not change the fact that the alcohol continues to dissipate from the defendant's bloodstream. The evidence sought "remains on a course to be destroyed." Krajewski, 255 Wis. 2d 98, ¶ 37. In Krajewski, we specifically rejected the contention that "the exigency *198exception to the warrant requirement.. . turn[s] upon the means used for executing the search rather than the urgency involved in the steady dissipation of alcohol." Id., ¶ 42 (emphasis in original). We also intimated that the exigency remained "[e]ven when a person submits to a breath test in lieu of a blood test" because the suspect could later challenge the test on the grounds that he did not freely and voluntarily consent to the test. Id., ¶ 41.
¶ 23. Thus, we conclude, based on the rationale of Bohling and Krajewski, that the presence of one presumptively valid chemical sample of the defendant's breath does not extinguish the exigent circumstances justifying a warrantless blood draw. "[T]he relevant basis for exigency here is that evidence is likely to be destroyed." Krajewski, 255 Wis. 2d 98, ¶ 36. Regardless of whether the police had obtained a breath sample from Faust, the evidence of intoxication revealed by the blood test was on a course towards destruction. The nature of the evidence sought, not the existence of other evidence, determines the exigency. We have found no authority that stands for the proposition that the police are limited to obtaining only a single piece of evidence under the exigent circumstances doctrine.9
*199¶ 24. In addition to being consistent with the nature of the exigency as described in Bohling and Krajewski, our conclusion comports with the underlying objective test for determining whether exigent circumstances exist. As noted supra, the test for whether exigent circumstances áre present is an objective one and inquires into whether the officer "might reasonably have believed that he was confronted with an emergency, in which the delay necessary to obtain a warrant, under the circumstances, threatened 'the destruction of evidence[.]'" Schmerber, 384 U.S. at 770 (quoting Preston, 376 U.S. at 367). Here, despite the *200presence of one presumptively voluntary and valid breath test, Officer Olsen might have reasonably believed that it was necessary to secure additional evidence of Faust's level of intoxication without a warrant in order to prevent needed evidence from being destroyed.
¶ 25. First, we recognize the police do not know when they administer a breath test whether the result of that test is valid and useable. In his concurrence, Judge Nettesheim indicated that appellate courts routinely hear a stream of challenges involving breath tests. Faust, 267 Wis. 2d 783, ¶ 23 n.3. As Judge Nettesheim stated:
[M]y concern is that the police do not have a crystal ball in these situations, a proposition which the Krajewski decision seems to recognize. While the police here presumably believed that they had obtained a valid breath test, this does not guarantee, in the very words of Krajewski, a satisfactory and useable breath test. That determination would depend on a future ruling by the trial court in the event that Faust should challenge the breath test.
Id., ¶ 22 (emphasis in original). Indeed, at oral argument counsel for Faust indicated that he planned to challenge the accuracy of the chemical breath test, due to medication that Faust was allegedly taking at the time of arrest.
¶ 26. Second, police often need to acquire additional, more definitive evidence of intoxication where the results of a chemical analysis of a breath sample are close to the legal limit. Here, the preliminary breath test indicated that Faust possessed an alcohol concentration of 0.13. Chemical analysis of the breath sample provided at police headquarters indicated an alcohol concentration of 0.09. While a search of Faust's criminal *201driving record indicated that he had two drunk driving related offenses and was thus subject to a prohibited alcohol content of 0.08, the police do not know in advance whether any of these prior convictions will ultimately be admitted into court. See Faust, 267 Wis. 2d 783, ¶ 23 (Nettesheim, J., concurring) (collecting cases where the defendant challenged alleged prior convictions). Had Faust ultimately successfully challenged one or both of his prior convictions — something the police had no way of knowing at the time the breath test was taken — the State would have had to prove that Faust operated his motor vehicle with an alcohol concentration of at least 0.1. See Wis. Stat. § 885.235(lg)(c). However, preliminary breath tests are not admissible at trial to prove the defendant's level of intoxication; they are only admissible at the probable cause hearing. Wis. Stat. § 343.303. Thus, the State would have been left with the results of the breathalyzer, which indicated that Faust possessed an alcohol concentration of only 0.09.
¶ 27. Third, even if the suspect has apparently complied with the implied consent statute and provided an initial chemical sample, there may later be an issue as to whether the defendant actually consented to take the test. State v. Rydeski, 214 Wis. 2d 101, 106, 571 N.W.2d 417 (Ct. App. 1997) ("[A] verbal refusal is not required. The conduct of the accused may serve as the basis for a refusal."). Likewise, there is no guarantee that the defendant will not argue at trial that the police coerced his or her consent to a test through use of the implied consent law or failed to properly administer the warning in Wis. Stat. § 343.305(4).10 Also, if a suspect *202consents to a blood test outside the parameters of the implied consent statute, there may later be an issue as to whether his consent was freely given. Krajewski, 255 Wis. 2d 98, ¶ 41. Therefore, the fact that the police had obtained a single presumptively valid breath sample from Faust did not remove the need to gather evidence of intoxication in light of "the urgency involved in the steady dissipation of alcohol." Krajewski, 255 Wis. 2d 98, ¶ 42.11 The threat remained that "evidence [would] be lost or destroyed if time [were] taken to obtain a warrant." Bohling, 173 Wis. 2d at 538.
¶ 28. Furthermore, we note the practical consequences that would ensue if we were to accept Faust's position that the exigency evaporates once the police have secured a single breath test that the officer believes to be voluntary and useable. First, as we explained in Krajewski, under Wisconsin's implied consent statute, § 343.305, "[a] person who operates a *203motor vehicle in this state is deemed to have given consent to one or more tests of his or her blood, breath, or urine upon the request of a law enforcement officer if the person is arrested for a drunk driving offense." Krajewski, 255 Wis. 2d 98, ¶ 19 (emphasis added).12 If we were to accept Faust's position, then when an individual arrested for drunk driving consents to the initial breath test and refuses all subsequent tests, the police would be compelled to obtain a warrant to conduct any additional test. As a result, "the arrested person would dictate the terms of investigation, limiting the police to a single option for a blood test — a search warrant." Id., ¶ 42.13
*204¶ 29. Second, as we noted in Krajewski, "[b]lood samples are the most direct means of measuring alcohol concentration in the blood.. . Id., ¶ 40. However, obtaining a warrant to authorize a blood draw may take some time and may often be impracticable. Id., ¶ 42 n.19.14 Police would be forced to choose between obtaining the most direct and accurate evidence of intoxication and taking the risk this evidence would be destroyed, or procuring the most easily ascertainable evidence of intoxication, knowing that it is often subject to challenge in court. Thus, such a result would impair the legitimate evidence gathering objectives of the police because the level of blood alcohol would continue to dissipate until the person is transported to a hospital and blood is actually drawn. See id., ¶ 38. Yet, as the United States Supreme Court recognized in Skinner, "[t]he government's interest in dispensing with the warrant requirement is at its strongest when, as here, 'the burden of obtaining a warrant is likely to frustrate the governmental purpose behind the search.'" Skinner, 489 U.S. at 623 (quoting Camara v. San Francisco Mun. Ct., 387 U.S. 523, 533 (1967)).
*205¶ 30. Ironically, Faust's position might also subject Wisconsin drivers to a greater number of blood tests. Because the police would be required to obtain a warrant to perform a nonconsensual blood test after a driver had consented to a breath test, police departments might routinely make a blood test the first test for which they ask under the implied consent statute so as to be able to gather the most direct evidence of a driver's level of intoxication without fear of the evidence being destroyed. Those stopped for an alcohol-related driving offense would be routinely subject to a blood test as a first test, a procedure far more time-consuming and intrusive than a simple chemical breath test. Skinner, 489 U.S. at 625-26.
B. Reasonableness
¶ 31. Although we have concluded that the nature of the evidence sought, not the existence of other evidence, determines the exigency, our holding does not mean that the police have carte blanche to take an unlimited number of tests as long as alcohol continues to dissipate from the bloodstream. We need not today determine the outer boundaries of the exigent circumstances exception to the warrant requirement and draw a bright line in order to answer questions such as whether the police may constitutionally take multiple blood tests or a combination of chemical breath samples, urine tests, and blood tests all without a warrant, for these are not the facts before us. As explained in Krajewski, "[ejxigency relieves the state of the burden of obtaining a warrant before a search. It does not relieve the state of establishing, in a hearing after the search, that it met the requirements for a constitutional search without a warrant, including the *206requirement of reasonableness." Krajewski, 255 Wis. 2d 98, ¶ 44. Thus, the mere presence of exigent circumstances is insufficient for a warrantless blood draw to pass constitutional muster; the search must also meet the test for reasonableness that we articulated in Bohling. Krajewski, 255 Wis. 2d 98, ¶¶ 45, 63; Bohling, 173 Wis. 2d at 533-34.15 Faust concedes that the test here satisfied the requirements set forth in Bohling.
¶ 32. As the United States Supreme Court has stated, "[t]he touchstone of the Fourth Amendment is reasonableness." Florida v. Jimeno, 500 U.S. 248, 250 (1991). "Reasonableness" pervades the test we set forth for evaluating the constitutionality of warrantless blood draws in Bohling. Bohling, 173 Wis. 2d at 533-34. There may well be circumstances where the police have obtained sufficient evidence of the defendant's level of intoxication that a further test would be unreasonable under the circumstances presented.
¶ 33. However, such are not the facts presented today. Here, the police obtained a chemical breath sample, the testing of which indicted that Faust pos*207sessed an alcohol concentration of 0.09. As noted supra, while the police were made aware after this test was performed that Faust had incurred two previous alcohol-related driving convictions, they could not know whether one or both of these convictions would ultimately be admitted at trial. If either of them were ultimately determined to be inadmissible, the State would be required to prove that Faust was operating his vehicle with an alcohol concentration of 0.1 or higher. See Wis. Stat. § 885.235(lg)(c). The preliminary breath test that indicated Faust possessed an alcohol concentration of 0.13 would not have been admissible for this purpose. Wis. Stat. § 343.303. Additionally, the police had no way of knowing at the time the test was administered whether the chemical analysis of Faust's breath sample would be useable at trial. Given the strong state interest in removing drunk drivers from Wisconsin's roadways (especially reoffending drunk drivers), Faust's two apparent drunk driving related convictions, and the results of the initial chemical breath test, we cannot say that requiring Faust to submit to a single warrantless blood draw was unreasonable.16
*208VI. CONCLUSION
¶ 34. In sum, we reaffirm that the rapid dissipation of alcohol in the bloodstream of an individual arrested for a drunk driving related offense constitutes an exigency that justifies the warrantless nonconsen-sual test of that individual's blood, breath, or urine, so long as the test satisfies the four factors enumerated in Bohling. The presence of one presumptively valid chemical sample of the defendant's breath does not extinguish the exigent circumstances justifying a war-rantless blood draw. The nature of the evidence sought —that is, the rapid dissipation of alcohol from the bloodstream — not the existence of other evidence, determines the exigency. Because exigent circumstances were present in this case and the blood test satisfied the test we set forth in Bohling, we reverse the decision of the court of appeals.
By the Court. — The decision of the court of appeals is reversed.
{dissenting).
¶ 35. I agree with the circuit court that the results of the forced blood test should be suppressed. The blood test was taken without consent, without a search warrant and without exigent circumstances.
¶ 36. Exigent circumstances did not exist, the circuit court ruled, because the arresting officer had already obtained what he believed to be a voluntary and *209sufficient breath test that demonstrated that Faust's BAC was in excess of the legal limit. The circuit court postulated that "the problem could have been obviated by [the law enforcement officer] purely requesting blood as the primary test."
¶ 37. The circuit court got the case right. It followed this court's decision in State v. Krajewski, 2002 WI 97, ¶ 40, 255 Wis. 2d 98, 648 N.W.2d 385, cert. denied, 537 U.S. 1089 (2002): "The exigency that exists because of dissipating alcohol does not disappear until a satisfactory, useable chemical test has been taken."
¶ 38. Law enforcement officers have a choice of which of several chemical tests to administer. As we explained in Krajewski, we must presume that the legislature had good reasons for giving law enforcement officers a choice among chemical tests. Each test has different attributes.1 Krajewski made it clear that the choice was the officer's, not the accused's. The chemical test the officer chose in the present case was, according to the officer's own testimony, a satisfactory, useable chemical test.
¶ 39. Adhering to the Krajewski case decided and published a mere two years ago, I conclude that, without consent, without a search warrant, and without exigent circumstances, the forced blood test in the present case violated the United States Constitution.
¶ 40. The Fourth Amendment provides: "The right of the people to be secure in their persons, houses, papers, and effects against unreasonable searches and *210seizures, shall not be violated".2 The crux of the Fourth Amendment is reasonableness.
¶ 41. "The United States Supreme Court has consistently held that warrantless searches are per se unreasonable under the Fourth Amendment, subject to a few carefully delineated exceptions."3 The majority relies upon the exigency exception to justify the war-rantless search in the present case, and its reasoning is broader than the exception.
¶ 42. The majority erroneously holds that the nature of the evidence alone determines whether exigent circumstances exist.4 The majority declares without any legal support at all, and contrary to our own Krajewski decision, that "[t]he nature of the evidence sought, not the existence of other evidence, determines the exigency."5
¶ 43. The accepted principle of law is that exigent circumstances are determined by examining the totality of the circumstances.6 The test for exigent circumstances upon review is whether a police officer under the circumstances known to the officer at the time "might reasonably have believed that he was confronted with an emergency, in which the delay necessary to *211obtain a warrant, under the circumstances, threatened the 'destruction of evidence.1 "7 •
¶ 44. Evidence of alcohol in the body is destroyed by the passage of time, without any act of the individual involved or of law enforcement. All evidence of intoxication cannot be gathered and preserved. Here evidence of intoxication has been preserved in the form of the result of a valid breathalyzer test. Evidence of intoxication that is being destroyed in the present case is cumulative of evidence already collected and preserved. The State offered no proof of exigent circumstances except for continuing dissipation of alcohol.
¶ 45. The majority's argument is essentially that because law enforcement officers do not know what will happen at trial (and no one does, of course), it was reasonable for them to take as many valid tests of the suspect's blood alcohol as they thought necessary to sustain a conviction.8 The majority also is concerned that a defendant may exercise his or her constitutional rights and challenge prior convictions or the validity of the results of a chemical test.9
¶ 46. This court understood and responded to these problems in Krajewski. The Krajewski court held that law enforcement officers may choose to give the chemical test they think appropriate under the circumstances.
¶ 47. Furthermore, the legislature apparently enables law enforcement officers to take more than one chemical test by request. Under the implied consent *212law, if the suspect refuses to submit to a chemical test, the police may take possession of the person's driver's license and prepare a notice of intent to revoke the person's operating privilege.10 Therefore, the state's interest in keeping drunk drivers off the road appears to be met, even if a warrantless blood draw is prevented by the Fourth Amendment.
¶ 48. Although the majority concedes that law enforcement officers do not have carte blanche to take an unlimited number of tests as long as alcohol continues to dissipate in the bloodstream, it refuses to define the outer limits of how many tests are reasonable. The majority opinion falls back to the reasonableness test, citing the four-part reasonableness test of Bohling.11
*213¶ 49. Bohling is not applicable to determine exigent circumstances in the present case when more than one test was administered. The first and second of the four Bohling factors amount to justification for arrest for drunk driving. The third factor relates to the setting under which blood is drawn. The fourth factor relates to exigent circumstances. But, according to the majority opinion, dissipation of alcohol creates exigent circumstances. So no reasonableness test is offered by the majority. The internal inconsistencies in the majority opinion are apparent and troubling.
¶ 50. By failing to define the outer limits of what is reasonable in a blood draw case, the majority opinion opens the door to more litigation. The majority opinion also leaves law enforcement officers, litigants, circuit courts, and the court of appeals in a quandary, without guidance regarding what number of tests is reasonable.
¶ 51. Because the breathalyzer test was sufficient to preserve evidence of Faust's intoxication until trial, no exigent circumstances existed to take blood without consent or a search warrant. That alcohol naturally dissipates in the blood ordinarily creates an exigent circumstance. It does not, however, create an exigent circumstance under the facts of this case.
¶ 52. For the reasons set forth, I dissent.
¶ 53. I am authorized to state that Justices ANN WALSH BRADLEY and DAVID T. PROSSER, JR. join this dissent.