Passing a drug test to file a person's taxes a certain way is irrelevant to the actual taxes themselves. This is a petty argument that if we test people who receive welfare benefits, we should test people at the other end of the income spectrum as well. What this idea fails to include is that drug use is not relevant to taxes or receiving benefits. Regardless of drug use, people deserve welfare benefits. Regardless of drug use, people have the right to file their taxes any way they might want. It doesn't actually matter who is or is not using drugs.