It is a frequently a challenge to determine if a student is under the influence of a prescribed or self prescribed narcotic. I have known students that tend to always look under the influence but that is their "norm". If I use the first student as a benchmark, I may be making bad assumptions. To be safe, I never accuse or confront a student; I will request that they remove themselves from a lab until I can determine it safe for them to return. It seems a little grey within our institution... do I request them to submit to a drug test, ask them to "drive" themselves to Wellspan or hold them hostage until I can summon Wellspan? Either way if the student tells me to pound sand then I feel I have no option. So what is the best choice, that protects the institution and myself from a lawsuit for harassment falsely accusing?