Maybe things have changed, but isn't it the case that trying to beat a employment-related drug screen is illegal some places, and has not been legislated upon in others? This is quite aside from the whole normative and moral dimension of course . . . I think there were two states in which selling things to interfere with drug tests is illegal . . . and as far as things being illegal, has the Constitutional question been definitively settled in the US anyways?
In this case, the orignal poster asked about a court-mandated periodic drugs screen, and the poster got the sage advice that they will make things easier for themselves by telling the truth instead of trying to conceal things with respect to a possible stimulant-use relapse, and doesn't wisdom in general help reduce harm? The system does or should know that relapses happen, and what they are wanting to reduce and prevent, in general, is dishonesty of various types, is it not?
Then again, there are urinalyses and other drugs tests done for legitimate medical reasons, like toxicology screens, the baseline and other screens that pain clincs and others do in order to make sure that they are not mixing medications with something incompatible, or there are Mao inhibitors floating around in a patients' system and that patient knows very little about drugs so he or she would have no idea.
For example, what about questions about the pharmacology which may be causing presumptive false positives for oxycodone in poppy seed tea drinkers? It could be either a glucuronide of codeine or a fourth or lower order metabolite of hydromorphone like 14β-hydroxydihydromorphinone or something if one has also been prescribed Dilaudid, Hydal &c as well, and on some occasions, the poppy or organisms associated with it create small amounts of hydromorphone in opium latex. Nothing illegal in that -- it is a straight phamacology question.