Defendants in DWI cases are supposed to be protected from being forced to submit to a blood test without a warrant unless they gave their consent to the test. The Supreme Court made clear it was a violation of the Constitution to force defendants to undergo a blood test unless police had first obtained a warrant.
Unfortunately, defendants do not always get this protection. This is because 13 states have made it a crime to refuse to take a blood test, and trends are moving towards other states imposing similar criminal penalties.
Now, however, the Supreme Court could put a stop to this trend (or exacerbate it) as the court has granted certiorari and has agreed to rule on cases affecting the rights of DWI defendants. The decision made by the court is an important one which could affect whether DWI defendants are actually protected by the constitution or whether their rights are abridged.
Supreme Court to Consider Rights of DWI Defendants
In 2013, the Supreme Court heard a case called Missouri v. McNeely. At issue in the case was the right of police to force a defendant to take a blood test even with no warrant, if the defendant didn't consent. While a warrantless forced blood test seemed to be clearly unconstitutional, the argument was made that exigent circumstances existed to justify a warrantless search. Police believed they should be entitled to take a test without a warrant, since the body was metabolizing the alcohol in the blood and destroying the evidence of a high BAC.
The Court fortunately ruled the body's metabolic processes were not an exigent circumstance justifying abridging the rights of defendants and forcing them to submit to a blood test. If police wanted to take a blood test, they'd either have to get a warrant or the driver would need to agree.
Unfortunately, the protections created in McNeely haven't always worked in practice because of the growing trend towards making refusal of blood tests a crime. Defendants are essentially told they must submit to a blood test or they will be charged with a criminal offense, so they don't really have an actual choice about whether to consent or not.
Defendants have been appealing and arguing the unconstitutionality of criminal statutes imposing penalties for blood test refusal. In Hawaii, the state Supreme Court recently held the criminal law in Hawaii was unconstitutional.
A defendant had been convicted of DWI for a BAC of .17, but his BAC was measured on a blood test taken with no warrant. The driver had only given consent to the blood test after he was told he could be sentenced to 30 days in jail otherwise. The court held the coerced consent wasn't real consent and the driver's conviction was thrown out.
The Hawaii case protects only defendants in Hawaii from criminal penalties- it doesn't protect defendants in other states with criminal laws or in states which could pass criminal laws for blood test refusal in the future.
If the Supreme Court holds it is unconstitutional to make consent to warrantless blood tests a crime, however, defendants will actually get real protection from being forced to take blood tests with no warrant. The two main cases being appealed to the Supreme Court are Bernard v. Minnesota and Birchfield v. North Dakota and the cases should be watched closely to see if DWI defendants are actually given the protections in the constitution.