How much privacy does the Constitution guarantee for the blood’s chemistry?

The Supreme Court, getting set for opening its new term, decided this week that it will take a serious look for the first time in nearly five decades at the constitutional privacy – or not – of individual’s blood chemistry.  The justices agreed to decide whether police can order that a blood sample be taken from a suspect, without first getting a judge’s approval to do so.

It is clear, under the Constitution’s Fourth Amendment, that government analysis of an individual’s blood or other bodily fluids is a “search” that can only be conducted within limits. Indeed, the court remarked in a blood search case in 1966 that “the integrity of an individual’s person is a cherished value in our society….Search warrants are ordinarily required…where intrusions into the body are concerned.”

But it was also in that very case – Schmerber v. California – that the court ruled that police can sometimes direct that a blood sample be made, in a drunk driving case, if there is an emergency situation that justifies the failure to first get a search warrant.   That is the ruling that the Court will be analyzing anew in the new term that starts next Monday, in a case from Missouri.

The issue of blood chemistry’s privacy arises often in cases involving suspected drunk driving.  But it can arise in other factual situations, too, and the degree of privacy for one’s blood is an abiding constitutional issue that has divided the lower state and federal courts.   The Supreme Court will attempt to provide some clear new guidance.

It is standard Fourth Amendment law that a search warrant is ordinarily required before police, or other government officials, may intrude into a private sphere or space.   But it is also a common understanding that, since the Fourth Amendment only bans searches that are “unreasonable,” it is reasonable to give police some leeway.   So there are exceptions to the usual requirement that they go to a judicial officer and get a warrant approved before actually carrying out a search.

One exception is a situation that the police regard as an emergency.   In legal terms, an exception to the warrant requirement is made when there are “exigent circumstances.”  One of those emergency-like situations arises when police fear that, if they take the time to get a warrant, vital evidence is likely to be destroyed.  If, for example, police enter an apartment where they have good reason to believe that illegal drugs are being sold, they need not get a warrant if there is a likelihood that the drugs will be flushed down a toilet before a warrant could arrive.

The new case in the Supreme Court, Missouri v. McNeely, involves a police officer in Cape Girardeau, Mo., who took a drunk-driving suspect he had arrested to a hospital and told the staff there to take a blood sample, after the suspect refused to permit it.   The officer said he understood he did not need a warrant, because of the fact that, as alcohol remains in the blood system, it begins to dissipate.  If one waits too long to test for the alcohol level, it may drop and the evidence of intoxication will be gone, the officer reasoned.

The Missouri Supreme Court said that, if the situation is not truly an emergency one, the mere fact that the alcohol level will drop over time is not sufficient reason to avoid getting a warrant.   It noted that there was no evidence in this case that a warrant was unavailable; the officer just thought he did not need one.

That court decided that the Supreme Court’s ruling in the Schmerber case in 1966 meant that lower courts are to look at all of the specific circumstances in a blood-draw case, to decide whether an officer was allowed to do without a warrant before ordering a hospital aide to draw a suspect’s blood.   The 1966 precedent, the state court said, “requires more than the mere dissipation of blood-alcohol evidence to support a warrantless blood draw in an alcohol-related case.  Officers must reasonably believe that they are confronted with an emergency where the delay in obtain a warrant would threaten the destruction of evidence.”

And, what the officers’ believe is an emergency is subject to second-guessing when the case gets to court, if they did not obtain a warrant.   It is better, the Missouri court said, for the ultimate judgment about the need for the sample be made by a neutral judge rather than by an officer on the scene.

The Supreme Court will consider that case, probably in January, and decide it during the current term that runs through next June.

Lyle Denniston is the National Constitution Center’s Adviser on Constitutional Literacy. He has reported on the Supreme Court for 54 years, currently covering it for SCOTUSblog, an online clearinghouse of information about the Supreme Court’s work.

Recent Constitution Daily Stories

The debate that changed the world of politics
Swing state Survivor: TV ads show three key states
Do politicians, courts have power to end NFL ref debacle?