forget all the dribble about why you should be allowed to stick your nose into their private life. have you throught about the logistics of getting a million people to piss into a cup, and test it every so many months?
your going to need to find 1,000 drug testers assuming each person does 300 a month and you check quarterly. plus your going to need to waste more time of the office clarks updating files.
its going to cost a few billion a year to achive nothing.