Is my old company guilty of anything?

So, I worked for a corporate truck stop gas station for about a day before severe training issues arose; that was settled on the basis that if the GM wants to try an everyone-for-themselves, sink-or-swim training approach, he has the precedent to do so. My question begins afterward – During my stay there, which included the hire, the day intro, and the first day on the floor, the corporation never ran a drug screen on me though they say in their contract that any employment is dependent first upon a negative drug screen. So, did they violate any laws by hiring me without a drug screen or something?