The easiest way for the State to prove impairment in a prosecution for impaired driving is by introducing the results of a test of the defendant’s breath. Such test results are admissible without the foundation that would otherwise be required for this kind of scientific evidence so long as the testing was carried out in accordance with statutory and administrative rules governing implied consent testing. G.S. 20-139.1(b). Because the rule allowing breath test results to be introduced into evidence is relied upon so often, I thought it might be helpful to review the admissibility rule and the requirements for such tests.
The U.S. Supreme Court waded into the murky waters of implied consent law this term in Birchfield v. North Dakota. The opinion it issued last week clarified important aspects of the relationship between chemical testing for impairment and the Fourth Amendment, but failed to distill a coherent theory of implied consent. Here’s what we know after Birchfield:
- Warrantless breath testing of impaired driving suspects is permissible under the Fourth Amendment as a search incident to arrest. A person who refuses to submit to such testing may be subjected to sanctions ranging from license revocation to criminal prosecution.
- Warrantless blood testing of impaired driving suspects is not permissible under the Fourth Amendment as a search incident to arrest. Thus, a warrant or a suspect’s consent is required to conduct such testing. A person who refuses to submit to such testing may not be criminally prosecuted for that refusal.
I admit that I may have a problem. I am dedicated to (perhaps obsessed with) the pursuit of a legal theory that satisfactorily squares the doctrine of implied consent with the Fourth Amendment. A thousand Westlaw searches later, I have yet to find analysis such an analysis by a court. So I was a little surprised when the United States Court of Appeals for the Eighth Circuit explained earlier this summer that the Supreme Court determined more than thirty years ago in South Dakota v. Neville, 459 U.S. 553 (1983), that implied consent testing carried out under threat of license revocation comported with the Fourth Amendment. Did I miss something?