I think the point is that marijuana will show up in a drugs days a few days later, even when you're no longer high.

As in, you wouldn't fire someone for showing up sober on Monday morning because they had a glass of wine on Saturday evening.

Urine drug tests don't test for active inebriation. They test for metabolite presence, which for cannabis can linger for up to a month depending on a number of factors. That's why drug testing is not the answer to your problem.

The hard drugs that tend to have more destructive effects don't even show up on a urine drug test for much longer than 72 hours. So, while the person who only smokes weed after work in the evening is at risk of being caught by a drug test, the person who gets off on Friday, goes on a cocaine binge, and then tests clean on Tuesday or Wednesday has nothing to worry about. Which would you rather have in your employ? I'd choose the pothead over the cokehead without hesitation.

Okay so lets start making daily breathalyzer tests standard for anyone who works in kids. Once in the morning and once after lunch.