The Assembly of States Parties (ASP) to the Rome Statute of the International Criminal Court (ICC) plays a significant role in relation to the ICC and, by extension, international criminal justice. Non-governmental organizations and some states have expressed concern about the potential for the ASP process to unduly influence the exercise of the judicial and prosecutorial functions of the ICC. This article uses three examples stemming from recent ASP sessions to analyse the ASP’s potential to influence the work of the Prosecutor and the Chambers of the ICC: (1) the ASP’s legislative function with reference to ASP changes to the ICC Rules; (2) the non-cooperation of Rome Statute parties with the ICC; and (3) the budget approval process. It argues that the ASP risks undermining the ICC’s judicial and prosecutorial independence. However, civil society participation in the ASP process, respect for the sub judice principle, and the development of an ultra vires doctrine could moderate this influence.