6 instrument of Article 25), in which new violations of due process may in turn occur, now in the venue of the protective proceeding established by the latter precept. Of course, it is also possible that this same instrument -habeas corpus, amparo and similar means- may be invoked to protect rights contained in all or almost all the provisions of the American Convention. 25. There is, therefore, a borderline that persists between legally protected interests and rights, in their respective hypotheticals, that may be analyzed separately. This judgment does that, for example, inasmuch as it studies abridgment of Article 25 from the standpoint of the violation of Article 7(6), regarding control over lawfulness of the detention. I do not set aside the hypothetical, more complex than the one I mention now, that there may be a distinction between the guarantees judge –or one acting as such-, who acts in the criminal trial itself, to ensure respect for legality regarding evidence and precautionary measures (which is another way to comply with the mandate of Article 7(6)) and the judge who oversees the lawfulness or constitutionality of actions by the authorities, established as a tribunal that is external to the criminal proceeding, and to whom one resorts based on Article 25 of the Convention and on the numerous domestic provisions that regulate this matter. 26. Regarding this same point, we must take into account that, under the terms of Article 27(2) of the Convention, there is the possibility of suspending the right to fair trial set forth in Article 8, but this possibility does not exist regarding those guarantees that are indispensable for the protection of the substantive rights whose suspension is forbidden, and these are precisely those mentioned in Article 25, as the Inter-American Court has pointed out in advisory opinions regarding amparo and habeas corpus and in adjudicatory matters in which this criterion has been applied. In this regard, we must consider, especially, Advisory Opinions OC-8/87, on “Habeas Corpus in Emergency Situations,” of January 30, 1987, and OC-9/87, regarding “Judicial Guarantees in States of Emergency,” of October 6, 1987. There is doubtless a need to take into account the requirements of due legal process when assessing compliance with Article 25. It would be unacceptable for the protection offered by this Article to be diminished or cancelled through procedures that disregard indispensable procedural rights before the habeas corpus or amparo jurisdiction. VI. Due process. 27. The Anglo-Saxon term due process -translated in some countries as “garantías esenciales del procedimiento” [essential procedural guarantees]- is one of the most formidable tools for protection of rights. It is also, in itself, a right and a guarantee for the defendant. It enables or realizes effective judicial protection. It involves access to formal justice, such as a hearing, evidence, and pleadings, and to material justice, as the means to obtain a just judgment. It entails clean and balanced use of the arms that both the accuser and the defendant are allowed to use, as well as objectivity, serenity, and the will of the court to give to each one what is due; in brief, fair trial. All these concepts, each of which has been characterized and positioned in the domestic legal systems, have a common denominator in their origin, development, and objective, and they come together under the concept of due process. 28. We had gained much ground in the endeavor for due process. The Court has referred to it –thus, for example, in Advisory Opinion OC-16/99, on “The right to information on consular assistance,” of October 1, 1999, to which I added a separate Opinion in which I analyzed this point- as a system of guarantees with expansive power. The static aspect of due process, sheltered in certain acts, rights, and guarantees that are non-revocable, has been reinforced by the modern dynamics of