Chapter 4 tests the delegation theory by applying it to a number of hypothetical case studies involving actual situations that have been considered by the ICC. Specifically, it uses scenarios that potentially involve procedural immunities to explore whether delegation of jurisdiction provides a legal basis for the ICC’s jurisdiction in different situations that could come before the Court via a State referral or Prosecutor-initiated investigation. The first case study is a hypothetical scenario in which a sitting Head of State from a non-State Party is wanted by the ICC for the commission of crimes on the territory of a State Party. Incumbent Heads of State are immune from prosecution in foreign domestic courts, which raises the question of how States Parties can be said to delegate jurisdiction to the ICC, when the exercise of such jurisdiction would be unlawful in the domestic context. The second and third case studies use the situations in Afghanistan and Palestine, each of which raises potential obstacles relating to curtailed domestic jurisdiction that could affect whether the ICC is able to lawfully prosecute nationals of non-States Parties for crimes committed on those territories.