Presumption of guilt before establishment of legal fact.
You MIGHT become a gigolo, since (I'm guessing), you have the equipment to become such. Can you be prosecuted as one just because you have the POTENTIAL to prostitute yourself?
'Impairment' is no different. The Founders established our country with the intention that the people were sovereign, and that a person had to actually be judged guilty of committing a crime before you could be punished for it.
Seeing the reverence in which you (rightfully) hold the Constitution on your homepage, one would think you would understand the document a little better before spouting off.
Prostitution harms nobody (and hence should itself be legal); putting others' lives at risk is another story. I can't agree that it should be legal to shoot into a crowd as long as you're lucky enough to miss them all.