Here’s the cite for the DWI holding in NC. http://nccriminallaw.sog.unc.edu/light-just-turned-yellow-retrograde-extrapolation/
Its all about scientific support, or lack there of in the appellate halls of North Carolina.
DWI ‘extapolations’ of BA to assume alcohol ‘eliminating’ phase at time of testing take a hit.
Thanks to GGWolk