The authors examine the effect of labor unions on workplace safety. For identification, they exploit the timing and outcome of union elections, using establishments in which elections narrowly fail as a comparison group for establishments in which elections narrowly pass. Data on elections come from the National Labor Relations Board, and data on workplace safety come from the Occupational Safety and Health Administration. The results indicate that unionization had no detectable effect on accident case rates at the mean, but shifted downward the case-rate distribution below 2 cases per 100 full-time equivalent workers annually. The downward shift is most evident among larger bargaining units and manufacturing establishments. Results at the higher end of case-rate distribution are inconclusive.

作者研究了工会对工作场所安全的影响。为了进行识别，他们利用选举失败的场所作为比较组来比较选举通过的时间和选举结果。有关选举的数据来自国家劳资关系委员会，有关工作场所安全的数据来自职业安全与健康管理局。结果表明，工会组织平均不会对事故发生率产生可检测的影响，但是将案件发生率分布向下移动到每年每100名全职同等工人中2例以下。在较大的讨价还价单位和制造机构中，这种下降趋势最为明显。病例率分布较高的结果尚无定论。