You are driving home from drinks with friends when you are stopped by the police. After you fail field sobriety tests, the officer asks you to agree to a breath test to measure your blood alcohol concentration (BAC). You decline.
California Field Sobriety Test
You are placed under arrest and taken to a nearby hospital. The officer asks you to agree to a blood test, telling you that in California, refusal to submit to a chemical blood or breath test can result in the automatic loss of your driver's license for a minimum of one (1) year.
You again say no.
Can the officer order a lab technician to take your blood without your consent? Can the police literally strap you down and forcefully take a blood draw?
Not without a warrant, the United States Supreme Court held in Missouri v. McNeely, unless there are specific exigencies that make obtaining a warrant impractical.
Otherwise, taking the blood of someone suspected of a DUI, without a warrant, may constitute a violation of that person's Fourth Amendment right to be free of unreasonable searches and seizures.
The warrant requirement is subject to exceptions, the court noted. One well-recognized exception is when the exigencies of the situation make the needs of law enforcement so compelling that a warrantless search is objectively reasonable under the Fourth Amendment.
But just because motorists have a diminished expectation of privacy in their cars, the court said, that does not diminish their privacy interest in preventing a government agent from piercing their skin. In routine DUI cases, police may need to seek a warrant.
In the case before the court, the defendant had been stopped by a Missouri police officer for speeding and crossing the center line. The officer noticed several signs that the defendant was intoxicated, including bloodshot eyes, slurred speech, and the smell of alcohol on his breath.
The defendant declined to take a breath test to measure his BAC. He was arrested and taken to a hospital for blood testing, which he also refused.
The officer did not attempt to get a warrant, but directed a lab technician to take his blood anyway. The test showed that defendant's BAC was well above the legal limit and the defendant was charged with driving while intoxicated in violation of Missouri statute 577.010.
The percentage of alcohol in an individual's blood typically decreases by approximately 0.015 percent to 0.02 percent per hour once the alcohol has been fully absorbed, testimony in the case established.
The state of Missouri argued that because BAC dissipates so quickly, there are inherently “exigent circumstances” whenever an officer has probable cause to believe that a person has been driving under the influence.
But the justices disagreed, saying that the mere fact that BAC dissipates quickly does not, in and of itself, constitute exigent circumstances that justify an exception to the warrant requirement for nonconsensual blood testing in drunk-driving investigations.
In some situations, the justices acknowledged, exigent circumstances may exist because obtaining a warrant may be impractical.
But in other situations, the warrant process will not significantly increase the delay before the blood test is conducted. As an example, the justices cited a situation in which an officer could take steps to secure a warrant while the suspect is being transported to a medical facility by another officer.
In such a case, they said, there would be no plausible justification for an exception to the warrant requirement.
In short, the court concluded, while the natural dissipation of alcohol in the blood may support a finding of exigency in a specific case, it does not do so categorically. Whether a warrantless blood test of a drunk-driving suspect is reasonable must be determined case by case based on the totality of the circumstances.
The case is Missouri v. McNeely, 569 U. S. ____ (2013).
Note that an arresting agency, not the DUI suspect, is responsible for the cost of DUI blood draws. Learn more in our article about California hospitals wrongfully charging DUI suspects for blood draws.)