According to most existing texts (conventions on privileges and immunities, headquarters agreements, and the like), intergovernmental organizations cannot be judged by any court of ordinary law unless they expressly waive that privilege. Even if they do so, their waiver cannot be extended to measures of execution. Complaints against intergovernmental organizations have therefore been dismissed by courts leaving complainants with no means of seeking redress.
Although this particularly exceptional situation may seem excessive it is expressly limited by the obligation imposed on international organizations to institute a judicial system for the settlement of conflicts and disputes in which they may become involved.
An example of non-resolution of disputes includes the decision of the New York County Supreme Court in the [Matter of Menon]. The estranged wife of a non-resident United Nations employee was challenging the refusal of family court judges to order the UN to show cause why her husband's salary should not be sequestered to provide support for herself and her minor child. The application was dismissed because the law specifically exempted a sovereign body from the jurisdiction of the USA courts, unless the sovereign consented to submit itself.
Once the first intergovernmental bodies were set up it became apparent that there was a need to afford them some protection against particular government authorities, especially judges and executive officials, capable of interfering with their operation. International organizations, lacking territory of their own, have to be based in the territory of a State. Being unable to enjoy the protection conferred by territorial sovereignty, international organizations have as their sole protection the immunities granted to them. The ample immunity afforded them is fully justified, in contrast to the increasingly restricted immunity of States, for the good reason that States are political entities pursuing their own interests while international organizations are service agencies operating on behalf of all their member States.