Drunk is High, HIgh is Drunk

Two States have passed laws making the use and possession of marijuana legal. Now, a whole bunch of question are coming up about workplace use, drug testing issues, use by police and more. Why do they think it will or should be treated any different than alcohol use? In any job, if you are drunk, you are fired. If you test positive for alcohol you get treatment or you get fired. If you fail a field sobriety test you get arrested and charged with DUI. Why does anyone think that being high in any of those circumstances should be treated any differently? Drunk? You are fired or arrested. High? You should be fired or arrested. No difference.