Driving While Intoxicated (Class B Misd-first offense) VS. Driving Under Influence (Class C Misd)
DWI: TX Penal Code 49.04 https://statutes.capitol.texas.gov/Docs/PE/htm/PE.49.htm
Operative definition:
(2) "Intoxicated" means:
(A) not having the normal use of mental or physical faculties by reason of the introduction of alcohol, a controlled substance, a drug, a dangerous drug, a combination of two or more of those substances, or any other substance into the body; or
(B) having an alcohol concentration of 0.08 or more.
DUI: TX Alcohol Beverage Code 106.041. DRIVING OR OPERATING WATERCRAFT UNDER THE INFLUENCE OF ALCOHOL BY MINOR. (a) A minor commits an offense if the minor operates a motor vehicle in a public place, or a watercraft, while having any detectable amount of alcohol in the minor's system.
if a person under the age of 21 is pulled over and has any alcohol in his system, then he or she can be charged with a "DUI" (or "DUIA," which stands for "Driving Under the Influence of Alcohol"). This is the only officially legal use of the term "DUI" in Texas.