In certain circumstances, yes, it is against the law. Care to tell us what circumstances they might be?
In certain circumstances, it is a crime to carry a gun, but that does not make carrying a gun, per se, illegal. We already talked about being asleep. Being stoned, per se, is not a crime in this country. "Certain circumstances" and "per se", do not delineate overlapping events, even if you hold your breath until you turn blue.