The spillover effects of health insurance benefit mandates on public insurance coverage: Evidence from veterans.

This study examines how regulations in private health insurance markets affect coverage of public insurance. We focus on mental health parity laws, which mandate private health insurance to provide equal coverage for mental and physical health services. The implementation of mental health parity laws may improve a quality dimension of private health insurance but at increased costs. We graphically develop a conceptual framework and then empirically examine whether the regulations shift individuals from private to public insurance. We exploit state-by-year variation in policy implementation in 1999-2008 and focus on a sample of veterans, who have better access to public insurance than non-veterans. Using data from the Current Population Survey, we find that the parity laws reduce employer-sponsored insurance (ESI) coverage by 2.1% points. The drop in ESI is largely offset by enrollment gains in public insurance, namely through the Veterans Affairs (VA) benefit and Medicaid/Medicare programs.