A party who brings a constitutional challenge to a statute must show that it is unconstitutional beyond a reasonable doubt. Additionally, in a facial vagueness challenge to the constitutionality of the law, Smith must establish, beyond a reasonable doubt, that there is no possible application or interpretation of the statute which would be constitutional. Furthermore, if the alleged conduct of a defendant plainly falls within the prohibition of the statute, the defendant may not base a constitutional vagueness challenge on hypothetical facts, unless a First Amendment right is at issue. Stated another way, a defendant who engages in some conduct that is clearly proscribed cannot complain of the vagueness of the law as applied to the conduct of others, absent an impact on a First Amendment right. And finally, if an actor's conduct plainly falls within the proscription of the law, he cannot make a vagueness challenge.
Vagueness is essentially a procedural due process concept which is driven by notions of fair play.
However, a statute is not void for vagueness simply because in some particular instance some type of conduct may create a question about its impact under the statute. In order to be void for vagueness under the first element, the statute must be so ambiguous that one who is intent upon obedience cannot tell when proscribed conduct is approached. Under the second element of enforceability, a statute is vague only if a trier of fact must apply its own standards of culpability rather than those set out in the statute. Furthermore, a statute is not unconstitutionally vague simply because it is ambiguous. When we are asked to apply a statute whose meaning is in dispute, our efforts are directed at determining legislative intent.