Consent searches that are coerced are not effective to surrender a constitutional right.

Consent searches that are  coerced are not effective to surrender a constitutional right.
a. Consent sufficient to waive a constitutional right must both be “‘the product of an essentially free and un- constrained choice by its maker’” (Schneckloth v. Bustamonte, 412 U.S. 218, 225 (1973)) and be revocable. Neither of those conditions is satisfied here.
In these circumstances, someone who will be denied the ability to drive unless he or she agrees in advance to submit to a chemical search can hardly be said to have “‘freely and voluntarily’” consented to such a search. Schneckloth, 412 U.S. at 222 (citation omitted).

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Consent searches trigger application of the unconstitutional conditions doctrine, which “vindicates the Constitution’s enumerated rights by preventing the government from coercing people into giving them up.” Koontz v. St. Johns River Water Mgmt. Dist., 133 S. Ct. 2586, 2594 (2013); see id. at 2596
States have available a wide range of other tools, including expedited warrant procedures and numerous mechanisms to keep impaired drivers from getting behind the wheel in the first place, that are more effective.
Thus, the Court’s decisions consistently “have determined that ‘[w]here a search is undertaken by law enforcement officials to discover evidence of criminal wrongdoing, reasonableness generally requires the obtaining of a judicial warrant.’” Riley v. California, 134 S. Ct. 2473, 2482 (2014) (ellipses omitted) (quoting Vernonia School Dist. 47J v. Acton, 515 U.S. 646, 653 (1995)). “Such a warrant ensures that the inferences to support a search are ‘drawn by a neutral and detached magistrate instead of being judged by the officer engaged in the often competitive enterprise of ferreting out crime.’” Ibid. (quoting Johnson v. United States, 333 U.S. 10, 14 (1948))

It is of course true that a person may consent to a search for which a warrant otherwise would be required. This “‘jealously and carefully drawn’ exception [to the warrant requirement] recognizes the validity of searches [undertaken] with the voluntary consent of an individual possessing authority” to give it. Georgia v. Randolph, 547 U.S. 103, 109 (2006) (citations omitted). This Court’s cases teach, however, that a valid consent must be “the product of an essentially free and unconstrained choice.” Schneckloth v. Bustamonte, 412 U.S. 214, 218, 225 (1973) (quoting Culombe v. Connecticut, 367 U.S. 568, 602 (1961)). That standard is not satisfied here.

Since McNeely, States have continued to expand their use of electronic warrants, a trend we can expect to continue. See, e.g., Fla. Stat. Ann. § 933.07 (West 2015) (allowing use of electronic warrants); Notice to the Bar, New Jersey Supreme Court (Nov. 14, 2013), perma.cc/B5BY-QF84 (authorizing the expanded use of electronic and remote “warrants for nonconsensual blood testing in all driving while intoxicated (DWI) cases where no indictable charge is anticipated”). For example, Arizona has achieved success in combating drunk driving through its pioneering use of electronic warrants, which can take fewer than fifteen minutes to process. Diana Hegyl, iCISng eSearch Warrant Application, Jud. Branch News 6 (Mar. 2013), perma.cc/BR6L-EB3S. In 2012 alone, Maricopa County Courts processed 10,510 electronic search warrants for the city of Phoenix. Although Arizona requires a warrant to compel a blood or breath BAC test (see State v. Butler, 302 P.3d 609, 613 (2013)) and does not have a criminal compelled-consent law, that State has a lower reported incidence of drunk driving than the national average. Drunk Driving US Map, Ctrs. for Disease Control & Prevention (Jan. 21, 2015), perma.cc/P5KM-J2ZZ.