Right-to-work laws, union decline, and the opioid crisis
利用美国四个州逐步实施工作权法的自然实验，结合合成控制法和双重差分法，发现工会率下降导致阿片类药物过量使用显著增加，且影响集中在工作条件恶化的劳动年龄男性。
Abstract A large literature links de-unionization to determinants of health, but direct evidence on objective health outcomes remains scarce. Exploiting the staggered implementation of right-to-work (RTW) laws across four US states, we quantify the role of union presence in opioid misuse. We combine the synthetic control method with staggered differences-in-differences to estimate time-varying effects. RTW adoption is followed by a persistent decline in unionization within 4 to 6 years, and this decline is associated with sizable increases in both nonfatal and fatal opioid overdoses, with no comparable changes for non-opioid drugs. Effects are concentrated among working-age men and align with channels tied to workplace conditions, including higher occupational risk, lower wages, longer hours, and elevated work stress. Taken together, the evidence indicates that the decline in unionization meaningfully contributes to the opioid crisis in affected states.