difficult child took a pre-employment drug test today at a temporary employment agency and failed it. He claimed he was clean, so they told him to go to a clinic and retake the test at his own expense, which he did (well, actually it was at my expense, but that's beside the point). Anyway, he passed the second test. I went with him for the second test, patted down his pockets myself, and heard him "go," so I don't think there was any way he brought in a sample from someone else and switched it. The nurse said the temperature of the sample was fine. And I figure if he was going to tamper with the results, he would have done it when he took the first test. However, since he is a difficult child, I'm still not 100% sure whether to rely on the negative result from the second test. Drug use isn't out of the question, especially pot, but he claims he doesn't use it (he has used it in the past, though, and has friends who do use it, which he does admit). We tested him ourselves in December, and he tested negative (that test was done at the above-mentioned clinic). Has anyone else run into this? This temp service is an agency we use where I work, and I've never had anyone fail one of their drug tests. difficult child said he failed another test at a different temporary service several months ago, and he says that's why he doesn't like to take drug tests at temp services. He would rather go to a clinic, because he says they're more accurate. Any input anyone has on this subject would be greatly appreciated.