RESUMEN
BACKGROUND: Rising nativism and political volatility worldwide threaten to undermine hard-won achievements in human rights and public health. Risks are particularly acute for hundreds of millions of migrants, minorities, and Indigenous peoples, who face disproportionately high health burdens, including HIV/AIDS, and precarious legal status (LS). While LS is receiving increasing attention as a social determinant of health and HIV, understandings are still limited to select immigrant communities. Its effects on health among stateless communities, particularly in the Global South, remain largely unknown. Moreover, widespread limitations in census measures of LS reduce its complexity to a simplistic citizen/non-citizen binary or insufficient proxies. Thailand's ethnolinguistically diverse highlander population experiences disproportionately high HIV prevalence and comprises one of the world's largest and most protracted cases of statelessness, an acute condition of precarious LS. As such, analysis of LS and health outcomes among highlanders is both critically warranted, and useful as a case study outside of the migration paradigm. METHODS: Drawing on the UNESCO Highland Peoples Survey II (2010), an unprecedented and unique cross-sectional census of highlanders in Thailand, we mobilize complex measures of LS in adjusted ordinal logistic regression models to assess how parent citizenship and LS adjudication over the early life course condition adult HIV knowledge-a key protective factor against transmission (n = 8079). RESULTS: Adjusted ordinal logistic regression on knowledge scores reveal that parent citizenship predicts odds of greater knowledge by 1.4- to 2.2-fold, depending on ethnic group. This is partially explained by divergent stages of LS adjudication between birth and adulthood, including successful birth registration and adult citizenship acquisition, along with secondary school completion. Precisely how these factors contribute to HIV knowledge varies by ethnic group. CONCLUSIONS: This study advances knowledge of LS outside of the migration paradigm, reveals heretofore unexamined connections between LS and access to public health information, and elucidates how instabilities in LS adjudication stages underlie health inequalities over the life course. Findings indicate that securing success in public health and human rights agendas requires attention to how states adjudicate and deploy LS in multiple stages across the life course to structure access and exclusion among migrant and non-migrant communities alike.