The Myth of Unions’ Overprotection of Bad Teachers: Evidence from the District–Teacher Matched Data on Teacher Turnover

Abstract

This article examines the relationship between teachers’ unions and teacher turnover in U.S. public schools. The trade‐off between teacher pay and employment predicts that unions raise the dismissal rate of underperforming teachers but reduce the attrition of high‐quality teachers, as the higher wages unions negotiate provide districts strong incentives to scrutinize teacher performance during a probationary period while encouraging high‐quality teachers to remain in teaching. Using the district–teacher matched data and a natural experiment, I find that, compared to less‐unionized districts, highly unionized districts dismiss more low‐quality teachers and retain more high‐quality teachers, raising average teacher quality and educational outcomes.