Compliance Behavior under Surveillance: Introduction of the Video Assistant Referee to European Football

This paper analyzes the effect of introducing the Video Assistant Referee (VAR) to European football. First, the setting allows for decomposition of the deterrence and monitoring effects in Becker’s (1968) model of crime. Second, I estimate the deterrence effect’s spillover outside the surveillance environment. Third, I find evidence of a much under-studied learning-by-punishment effect. This paper applies the difference-in-difference strategy to show that the introduction of VAR causes a significant decrease in the number of fouls in two German football leagues. VAR had an immediate impact on severe fouls, while the effect on penalty fouls is apparent after a 12 week adjustment period. Punishment intensifies the deterrence effect as punished players commit even fewer fouls than unpunished players. Moreover, the deterrence effect persists outside of the surveillance environment, i.e., there is a spillover effect on international competitions. I show that players from countries with VAR commit fewer fouls in international competitions than other players.