Fuenning v. Superior Court
In Fuenning v. Superior Court, 139 Ariz. 590, 680 P.2d 121 (1983), the defendant challenged the basic DUI statute in existence at the time of his arrest, former A.R.S. 28-692, which proscribed driving "while there is .10 per cent or more . . . of alcohol in the person's blood."
Rejecting the concept that the statute inhibits any fundamental constitutional right, such as a right to ingest alcohol and then drive a vehicle, the court applied a traditional "vagueness" analysis and determined that, because the statute provided fair notice of what constituted a punishable BAC level, "it should not be declared void for vagueness simply because it may be difficult for the public to determine how far they can go before they are in actual violation" of the law. Fuenning, 139 Ariz. at 598, 680 P.2d at 129.
The court further explained:
While a driver may not be able to determine that his BAC is .10%, rather than .099%, such precision is not required to prevent the statute from being declared vague.
Due process requires neither perfect notice, absolute precision nor impossible standards. It requires only that the language of a statute convey a definite warning of the proscribed conduct. Id.