It has been argued that in order to reduce serious industrial accidents in the workplace, the responsibility and punishment of employers and management executives need to be strengthened. In accordance with this argument, the Serious Accidents Punishment Act has been enacted and implemented. Using a game-theoretic analysis, this paper shows that simply strengthening the responsibility of employers and management executives does not guarantee a reduction in accidents and that the control that employers and management executives have over workers should be considered to analyze the impact of the Act on the occurrence of accidents and social welfare.