Originally Posted by Lou_Zare
you don't understand the science behind your statement. It is complex, and I'm no expert so I'll just leave it at "it doesn't work this way".
I don't fully understand it either, but I know for sure it's tougher than a BAL test like a DUI. For whatever reason, it stays in your blood at reasonably high levels far after you are no longer "high" and it's difficult to define a cutoff in a way that would be an accurate predictor of impairment.
Or something like that.