Urine drug screening (UDS) is used in the care of patients with opioid use disorder, and for patients receiving opioids for chronic pain. There's no strong evidence that testing helps patients, however, and no consensus on what to do with the results anyway. These tests, often mandated, may cause serious harm when physicians don't realize how often there are false positives or react punitively by cutting off treatment. Testing can resemble a criminal justice encounter, where failing could result in jail time. In a conversation with an expert, we reflect on how urine tests can be helpful, but only if we understand what our role as a physician is in caring for vulnerable, marginalized, and traumatized patients who desperately need us to care about them.