In Schmerber v. State of California (1966) 384 U.S. 757, the Supreme Court held that a forcible warrantless blood draw from an arrestee does not violate the Fourth Amendment when "(i) the test is incident to a lawful arrest for driving under the influence of alcohol or a drug, (ii) the circumstances require prompt testing, (iii) the arresting officer has reasonable cause to believe the arrestee is intoxicated, and (iv) the test is conducted in a medically approved manner." (Troppman v. Valverde (2007) 40 Cal.4th 1121, 1136, citing Schmerber, supra, at pp. 766-772.) In Schmerber, the court explained: "The officer in the present case . . . 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,' citation. We are told that the percentage of alcohol in the blood begins to diminish shortly after drinking stops, as the body functions to eliminate it from the system. Particularly in a case such as this, where time had to be taken to bring the accused to a hospital and to investigate the scene of the accident, there was no time to seek out a magistrate and secure a warrant. Given these special facts, we conclude that the attempt to secure evidence of blood-alcohol content in this case was an appropriate incident to petitioner's arrest." (Schmerber, supra, 384 U.S. at pp. 770-771.) In Schmerber, the court held that because the blood-alcohol level diminishes rapidly, and because "time had to be taken to bring the accused to a hospital and to investigate the scene of the accident, there was no time to seek out a magistrate and secure a warrant." (Schmerber, supra, 384 U.S. at pp. 770-771.)