How Partisan Policies Can Shape Health Behaviors: Executive Order Proof-of-Vaccine Mandate Bans Increased COVID-19...

COVID-19 vaccine resistance was detrimental to herd immunity and worsened COVID-19 morbidity and mortality during outbreaks. Despite more evidence showing reactionary behavior among residents exposed to vaccine mandates, little research has been conducted on the effects of state proof-of-vaccine (POV) mandate bans in the United States (US). We sought to investigate the causal effects of POV mandate bans, overall and stratified by policy passage via executive order or state legislature, on first-dose COVID-19 vaccinations.

In the contiguous US, 21 states enacted POV mandate bans from 8 February 2021-25 October 2021. Using a geographic regression discontinuity design, we selected treatment and control counties within 150 miles of the POV mandate ban state border. The resulting sample was 4612 county-observations and 2466 unique counties. We conducted two-way fixed-effects estimation to compare changes in weekly, first-dose COVID-19 vaccinations among individuals <65 years old before and after POV mandate ban enactment between treatment and control counties.

Among executive order POV mandate ban counties, we saw an additional increase in weekly, first-dose COVID-19 vaccinations following POV mandate ban enactment when compared to controls. There was an additional 38.2% increase in Weeks 1-2, 40.6% in Weeks 3-4, 41.3% in Weeks 5-6, and 43.9% in Weeks 7-8.

While seemingly counterintuitive, these findings follow Psychological Reactance Theory. Once the perceived threat to freedom was removed, reactance to COVID-19 vaccinations declined and constituents received the COVID-19 vaccine of their own volition. Future public health efforts should consider potential reactance to mandatory policies and tailor efforts to community values.