Systems and methods for risk and fraud mitigation are presented. According to one or more aspects of the disclosure, a plurality of transactions may be processed without applying one or more active fraud rules. A hit rate for at least one fraud rule of the one or more active fraud rules then may be determined. Thereafter, a positive hit rate for the at least one fraud rule may be determined based on fraud event data corresponding to the plurality of transactions. In some arrangements, each transaction of the plurality of transactions may be randomly selected, from a larger plurality of received transactions, for inclusion in the plurality of transactions to be processed without application of the one or more active fraud rules. Additionally or alternatively, in certain arrangements, one or more fraud rules may be activated or deactivated based on their corresponding hit rates and positive hit rates.