Enforcement Design and Targeted Deterrence in Professional Sports: Evidence From NBA Anti‐Flopping Reforms

ABSTRACT This paper examines strategic responses to alternative enforcement designs in professional basketball. Using NBA player‐level panel data, we study two anti‐flopping reforms: ex post financial fines introduced in 2012–2013 and in‐game technical fouls implemented in 2023–2024. We estimate before‐and‐after models with player fixed effects, allowing responses to vary with pre‐reform foul‐drawing intensity. Because flopping is not directly observed in public data, we use shooting fouls drawn per game as our main proxy. We find a clear compression of the right tail of the foul‐drawing distribution after both reforms. Players with higher pre‐reform shooting foul‐drawing rates reduce them by 0.20 to 0.40 fouls per game relative to lower‐exposure players, whereas league‐wide averages remain largely unchanged. Event‐study evidence suggests that the 2023 reform is followed by a sharp reversal of pre‐existing trends, whereas the 2012 reform appears to reinforce an ongoing adjustment. Within a unified framework, we do not find statistically significant differences in deterrent effects between financial and in‐game sanctions. Overall, the results highlight the importance of enforcement design when the regulated behaviour is imperfectly observed.