Search the phrase “per se DWI North Carolina,” and the results look deceptively confident. AI summaries and legal directories will tell you that if your blood test hits a 
certain number, a conviction is inevitable.
That framing is not the law of North Carolina.
This post continues the Breath, Blood, and Bull series, which explores how science, technology, and human judgment shape DWI 
enforcement in North Carolina.
The first article examined the limits of field sobriety testing. This installment turns to the machines that translate breath into evidence, using “breathalyzers.”
By unpacking how they measure alcohol, where they can fail, and how lawyers challenge their results, you’ll see why science is not necessarily as simple as a number on a printout.
Carolina Criminal Defense & DUI Lawyer Updates