We examine the effect of Amnesty Plus and Penalty Plus on firms' initial selfreporting decision, in one market, by altering their whistle-blowing incentives in another market. Amnesty Plus and Penalty Plus are proactive US strategies which aim at triggering multiple confessions by increasing the incentives of already convicted firms to report in a second market where they collude. Predictably, conditional on the conviction of one cartel, Amnesty Plus and Penalty Plus strengthen firms' incentives to report the remaining cartel. However, Amnesty Plus and Penalty Plus have an ambiguous impact on firms' incentives to apply for amnesty in the first place: On the one hand, Amnesty Plus and Penalty Plus may help to sustain a cartel, otherwise reported under the EC Leniency Program. On the other hand, Amnesty Plus and Penalty Plus may induce immediate reporting of both cartels whereas only one of them would have been reported under the EC Leniency Program.