Governments and private firms have sought to regulate online piracy through legislation, police enforcement, and lawsuits. This article evaluates the effectiveness of large-scale police operations that targeted the warez scene, the community of hackers responsible for much of the copyrighted content illegally distributed online. Using interrupted time series, we find no significant direct or indirect impact of large-scale police operations on the warez scene. We explain the lack of direct impact by the number of arrests made during the police operations. We explain the indirect impact of police operations by the high turnover of warez groups, the vacuum created by the removal of large, established warez groups, the online nature of the warez scene, and the constrains in deterrence power online.KEY WORDS: police operations, impact of police operations, warez, interrupted time series, deterrence, intellectual property fraud