Many people are confused when looking at websites - or trying to do their own research - when they see the offense of driving while you are drunk referred to sometimes as driving while intoxicated, and other times as driving under the influence. So which is it - DWI or DUI?
The answer depends on where you are at. If you're in Texas, the offense is DWI or Driving While Intoxicated. The offense is found in Section 49.04 of the Texas Penal Code, which simply says "a person is intoxicated while operating a motor vehicle in a public place". In other states, the offense is referred to as Driving under the influence, or DUI.
As with most statutes, intoxication is defined - in Section 49.01; it means "not having the normal use of mental or physical faculties by reason of the introduction of alcohol, a controlled substance, a drug, dangerous drug, or combination of two or more those substances, or any other substance into the body." It also includes having an alcohol concentration of more than .08 in your blood, but that's another discussion.
Two Different Legal Definitions
There are two parts of that definition that are important. One is that you are only "intoxicated" when you've lost the normal use of mental or physical faculties", which many states would define as "under the influence". The other important part of the definition is that you can be intoxicated by doing more than drinking, such as taking drugs while you are drinking. That means you can get charged with DWI even if you take the test and it comes back under .08 - again, another discussion.
The difference really comes down to whether you want to refer to someone as "intoxicated" or "under the influence". Most people generally think of intoxication as being drunk, but as you can see from the definition it encompasses more than that. It probably makes more sense to describe someone as "under the influence" when they've had too much to drink or too much of anything else, but we always need to do things different in Texas. And besides, intoxicated does sound much more redneck and country than under the influence.
But that's not the end of the explanation. There is an offense of driving under the influence, but it's limited to people under 21. Since you cannot drink until you're 21 - at least you're not supposed to - you also shouldn't be drinking and driving - even if you're not intoxicated. Section 106.041 of the Texas Alcoholic Beverage Code makes it a crime for someone under 21 to operate a vehicle (which includes a boat) while having any "detectable amount of alcohol" in their system. Fortunately, it's a class C misdemeanor so you can't get sentenced to jail, but it does have some rather severe consequences on your license.
So if you're at a party you know the answers to several trivia questions. If some drunk guy starts telling you there's no such thing as DUI in Texas, you can tell him yes there is. And remember, we don't say "drunk".