: This research develops a Bayesian methodology in order to differentiate between legal statuses of non-immigrant citizens (green-card holder, temporary lawful resident, and undocumented) in national data and uses the methodology to analyze key policy issues regarding access to public and employer-provided health insurance by non-citizen immigration status. The proposed research fulfills the AHRQ's strategic research goal of increased efficiency and reduced cost in health care services, and focuses directly on one of its priority populations, low-income and minority groups. ? ? ?