The Impact of Free Agency on Competitive Balance in North American Professional Team Sports Leagues

Free agency was reintroduced to professional team sport leagues in the 1970s. Sport enthusiasts expressed concern that competitive balance would diminish as star players congregated to large market cities. However, the economic invariance principle rejects this notion, indicating that balance should remain unchanged. This article empirically examines the effects of changes in free agent rules on competitive balance over time in the National Basketball Association (NBA), National Football League (NFL), and National Hockey League (NHL). Regression analysis using within-season and between-season measures of competitive balance as dependent variables provides mixed results. The NFL and NHL provide evidence that an aspect of competitive balance has improved, but results from the NBA indicate that balance has worsened since the introduction of free agency. We conclude that the ambiguous results suggest that the effects are not independent, but instead depend on the interaction of free agent rights with other labor market and league rules.