in the exercise of their functions, they are also protected by the following guarantees: (i) guarantees of appropriate appointment; (ii) to irremovability from office, and (iii) to be protected against external pressures” (paragraph 79). 24. It is bearing this in mind that I stress the special importance of safeguarding the independence of prosecutors in order to preserve the rule of law. This has already been developed by the Court in the case of Martínez Esquivia v. Colombia, in which it concluded that the guarantee of stability and irremovability of judges, addressed at safeguarding their independence was applicable to prosecutors owing to the nature of their functions. This assertion is especially significant in the inter-American environment where, in recent decades, almost all the countries have put in practice adversarial systems of criminal investigation. The impartiality of the Public Prosecution Service is essential to avoid arbitrariness and to ensure fairness in the exercise of criminal investigations. 25. Those who work in public service are also encompassed by the right to work. I emphasize the provisions of the International Labour Organization’s Convention 151 on Labour Relations (Public Service), 1978.9 Article 9 of the Convention recognizes the civil and political rights of public employees and indicates that: “Public employees shall have, as other workers, the civil and political rights which are essential for the normal exercise of freedom of association, subject only to the obligations arising from their status and the nature of their functions.” Also, Article 8 of this Convention establishes that the settlement of disputes, “shall be sought, as may be appropriate to national conditions, through negotiation between the parties or through independent and impartial machinery, such as mediation, conciliation and arbitration, established in such a manner as to ensure the confidence of the parties involved.” 26. With regard to the instant case, Mr. Casa Nina, as a prosecutor which is a public official, also receives a protection of labor law in the exercise of his functions, and the analysis made in the judgment is appropriate. Taking into account the provisions of Convention No. 151, it is important to emphasize the protection of the civil and political rights of public officials and the recommendation as regards the settlement of disputes concerning working conditions or the permanence in office using systems of collective bargaining or others such as mediation. Owing to his dual condition as a public official and a prosecutor, the victim enjoyed the essential legal protection to be able to exercise his functions with independence, a guarantee that is intrinsically related to the democratic rule of law. 27. The foregoing is complemented by the United Nations “Guidelines on the Role of Prosecutors” mentioned in the judgment, which establish the status and conditions of services of those who are appointed as prosecutors, establishing that “States shall ensure that prosecutors are able to perform their professional functions without intimidation, hindrance, harassment, improper interference or unjustified exposure to civil, penal or other liability."10 The principle of independence of the public functions of the prosecutor may also be interpreted based on the “Basic Principles on the Independence of the Judiciary” adopted by the Seventh United Nations Congress held in Milan from August 26 to September 6, 1985.11 and costs. Judgment of July 5, 2006. Series C No. 150, para. 81, and Case of Zambrano Vélez et al. v. Ecuador. Merits, reparations and costs. Judgment of July 4, 2007. Series C No. 166, para. 122. International Labour Organization. Convention 151 on Labour Relations (Public Service), 1978. Available at https://www.ilo.org/dyn/normlex/en/f?p=NORMLEXPUB:12100:0::NO::P12100_ILO_CODE:C151. 9 Guidelines on the Role of Prosecutors. Adopted by the Eighth United Nations Congress on the Prevention of Crime and the Treatment of Offenders, Havana, Cuba, August 27 to September 7, 1990. UN Doc. A/CONF.144/28/Rev.1, para. 4. https://www.ohchr.org/en/professionalinterest/pages/roleofprosecutors.aspx. 10 “Basic Principles on the Independence of the professionalinterest/pages/independencejudiciary.aspx. 11 6 Judiciary,” available at: https://www.ohchr.org/en/