Truth: You can’t always trust the science of a drug test. There are many ways to challenge a military drug test. Tests are administered by human beings, and people make mistakes. Labs make mistakes. Machines make mistakes. Some positive results are “false positives.” Sometimes a valid prescription can make a person test positive for an illegal drug. You need an attorney who understands all these things, isn’t afraid of a positive test, and knows how to cross-examine the government’s toxicologist.