The Missouri Supreme Court is deciding that very question this fall in State of Missouri v. McNeely.  The case was transferred from the Missouri Court of Appeals for the Eastern District on June 21, 2011.

Before transferring the case, the Eastern District expressly stated what its opinion would be had it not transferred the case:

In its sole point, the State argues the trial court erred in granting Defendant’s motion to suppress the blood sample seized from Defendant’s person after he was arrested for driving while intoxicated because the sample was taken without Defendant’s consent and without a search warrant.  We would reverse; however, in light of the general interest and importance of the issues involved, we transfer the case to the Missouri Supreme Court, pursuant to Supreme Court Rule 83.02.

The case surrounds an incident that occurred last October when a man was pulled over in Cape Girardeau County, Missouri for a possible DWI.  Like most police officers, the patrolman claimed to smell a strong odor of alcohol and that the man had glassy and bloodshot eyes (this is always an easy fallback when the officer has no other evidence that you were drinking).

The man performed “poorly” after four field sobriety tests.  After the man refused a breath test, the officer took him to a clinic to have a blood sample taken.   The crucial part of the case is that the blood was taken without the man’s permission.  The man’s blood alcohol turned out to be a .154, which is nearly twice the legal limit.

The trial court ruled the case did not involve exigent circumstances, saying the Fourth Amendment required either a warrant or exigent circumstance to withdraw blood without consent.  The court of appeals has punted, now leaving it to the Missouri Supreme Court to decide.

As ridiculous as it sounds, I think the Missouri Supreme Court is going to decide on the side of the police on this one.