The injured party, that is, the claimant, also called the complainant, the petitioner or the plaintiff, in principle is the person having the constitutional right that has been violated; a situation that gives him a particular interest in bringing the case before a court. That is why the amparo action has been considered as an action in personam through which, seeking for the protection of constitutional rights, the plaintiff must be precisely the injured or aggrieved person.

That is why it is generally considered that the Latin American amparo action, in the same sense as the action for injunction in the United States, needs to be personalized, in the sense of being attributed to a particular person that because enjoying the harmed right, has a justiciable interest in the subject matter of the litigation, or a personal interest in the outcome of the controversy.

It is in this sense that the Nicaraguan Amparo Law provides that only the aggrieved party can file the amparo action, defining as such, “any natural or artificial person whose constitutional rights are harmed or that are in a situation of imminent danger of being harmed by any disposition, act or resolution, and in general, by any action or omission from any public officer, authority or its agent” (Article 23).