Association for Public Policy Analysis & Management

Recent research has shown that concern about the apprehension and deportation of undocumented immigrants can affect how other members of their households, otherwise eligible for public benefits, choose to participate in public programs. The extent to which this “chilling effect” broadly impacts health insurance enrollment nationally among adults remains unclear, in part due to the difficulty of isolating undocumented immigrants in survey data. In this study, we identified households that likely included undocumented immigrants and then examined whether gains in health care coverage due to the implementation of the Affordable Care Act (ACA) were dampened for eligible individuals living in households with mixed immigration status. We found there were no statistically significant differences in coverage gains associated with state expansions of Medicaid eligibility or availability of federally subsidized private coverage for individuals in mixed- relative to non-mixed-status households. Coverage gains were significantly lower, however, for individuals in mixed-status households in non-expansion states. These findings suggest that household immigration status may have “chilled” the “woodwork effect,” whereby the ACA enhanced knowledge about program availability, increasing Medicaid enrollment in non-expansion states among individuals previously eligible for the program, but not enrolled.