Emergency clinicians frequently care for patients with complications from underlying opioid use disorder. While many clinicians are comfortable addressing the immediate medical complications of opioid use disorder, too many do not offer evidence-based medications that stabilize the patient by alleviating withdrawal and cravings, and that also treat opioid use disorder, the underlying cause of the presentation. Because medication for opioid use disorder, namely methadone and buprenorphine, reduces the risk of death by up to 50%, this omission at a critical touchpoint in the health care system misses an opportunity to engage people in care and reduce fatal overdose. It also exposes the emergency department and health care facility to potential legal liability. Under federal civil rights laws, it is illegal to discriminate against people with opioid use disorder; discrimination may include failure to screen for and diagnose opioid use disorder and offer medications for opioid use disorder alongside a facilitated referral for outpatient treatment. Advocates for a more effective emergency department response to opioid use disorder can use these civil rights laws to press for the adoption of evidence-based practices for people with opioid use disorder. Legal advocacy is an important tool to utilize during this unrelenting overdose crisis.