Legal disputes over worldwide and U.S. sexual abuse by Catholic priests, and over efforts by Catholic bishops to conceal clerical misconduct, have produced many headlines and public discussion. However, the precise legal issues involved remain a mystery to most observers. In this study, James O'Reilly and Margaret Chalmers examine the role of canon law in these cases and the interplay between the global church-based law and the laws of individual jurisdictions where criminal actions and lawsuits are brought.