Missouri v. McNeely and Exigent Circumstances to Conduct Blood Tests for Drunk Driving Cases

Today the Supreme Court handed down Missouri v. McNeely, a Fourth Amendment case involving whether the government needs a warrant to draw blood after a suspect’s arrest for drunk driving to determine the suspect’s alcohol level. The Court held that whether a warrant is required “must be determined case by case based on the totality of the circumstances” to determine if the government could have obtained a warrant “within a reasonable amount of time” or if obtaining a warrant would “produce unacceptable delay” in light of the exigency of the dissipating alcohol levels in the arrestee’s blood.

So how do the police know when they need a warrant to conduct a blood draw following a drunk driving arrest? The majority starts with this general guidance: If the police can “reasonably obtain a warrant before a blood sample can be drawn without significantly undermining the efficacy of the search, the Fourth Amendment mandates that they do so.” On the other hand, if case by case circumstances “make obtaining a warrant impractical such that the dissipation of alcohol from the bloodstream will support an exigency justifying a properly conducted warrantless blood test,” no warrant is needed.

So that’s the general guidance. How about specifics? Here’s one piece of guidance the majority offers on when a warrant must be obtained:

[In] a situation in which the warrant process will not significantly increase the delay before the blood test is conducted because an officer can take steps to secure a warrant while the suspect is being transported to a medical facility by another officer[, . . ]there would be no plausible justifica­tion for an exception to the warrant requirement.

More broadly, the issue seems to be how much delay is introduced by getting a warrant. Can the officers get the warrant “within a reasonable period of time”? If the jurisdiction allows telephone warrants, or otherwise has ways to get warrants quickly, then that ability will push in the direction of needing a warrant:

[T]echnological developments that enable police officers to secure warrants more quickly, and do so without undermining the neutral magistrate judge’s es­sential role as a check on police discretion, are relevant to an assessment of exigency.

On the other hand, if the warrant process becomes delayed, then exigent circumstances may come to exist:

While experts can work backwards from the BAC at the time the sample was taken to determine the BAC at the time of the alleged offense, longer intervals may raise questions about the accuracy of the calculation. For that reason, exigent circumstances justifying a warrantless blood sample may arise in the regular course of law en­forcement due to delays from the warrant application process.

The standard thus requires each officer to have a good sense of how long it would take to get a warrant in a particular setting, as well as how quickly the evidence is needed given the exigency of the dissipating alcohol in the blood:

[B]ecause “[t]he police are presumably familiar with the mechanics and time involved in the warrant process in their partic­ular jurisdiction,” post, at 8 (opinion of ROBERTS, C. J.), we expect that officers can make reasonable judgments about whether the warrant process would produce unacceptable delay under the circumstances.

A few quick thoughts:

1) At the time of the cert grant, it was widely expected that this case would be an easy win for the government. It’s somewhat surprising that the Court rejected the government’s proposed bright-line test. This is more evidence of my view that there is a rights/remedy distinction in how the current Supreme Court approaches Fourth Amendment cases. If the case is about remedies, the government pretty much always wins. But if the case is about Fourth Amendment rights, the current Court can be hard to predict.

2) It will be interesting to see if this issue will end up back at the Court in a few years to resolve the various ways that lower courts are likely to apply this general guidance. I suspect it will.

3) There is a long-running dispute between the use of rules vs. standards in the interpretation of the Fourth Amendment. Today’s case is a big win for standards, all the more interesting because Justice Scalia was in the majority.

4) I see echoes of Arizona v. Gant in today’s decision. The Court divided 5-4 in adopting a defense-friendly narrow interpretation of a decades-old precedent, adopting a standard instead of a bright-line rule sought by the government that reflected how many courts had interpreted the prior precedent. The line-ups are somewhat similar, too. Not identical, but similar.