51 seek a legal purpose and be suitable, necessary and proportional. The Tribunal notes that the penalty of imprisonment imposed on Mr. Vélez Loor by means of Order 7306 (supra para. 94) was based on Article 67 of Decree Law 16 of 1960, which was issued on June 30, 1960 by the President of the Republic, upon having heard the favorable opinion of the Cabinet and prior approval of the Permanent Legislative Commission of the General Assembly.177 None of the parties questioned if this provision satisfied with the principle of legal exception, in accordance with this Tribunal’s jurisprudence.178 Hence the Court does not count with sufficient elements to make a declaration on this issue. Lawful purpose and suitability of the measure 168. As to the possibility of setting limitations or restrictions to the right to personal liberty it is necessary to note that, unlike the European Convention for the Protection of Human Rights and Fundamental Liberties,179 the American Convention does not establish, neither explicitly or implicitly, the reasons, cases, or circumstances that shall be considered lawful in a democratic society to authorize a custodial measure within the domestic legislation. 169. As has been already established, States have the authority to control and regulate the entrance and stay of foreign persons in their territory (supra para. 97); therefore, this may be a lawful purpose according to the Convention. In this respect, the application of preventive custody may be suitable to regulate and control the irregular immigration in order to ensure that the individual appears before the immigration proceeding or, in addition, to guarantee the application of an order for deportation. However, and in the view of the Working Group on Arbitrary Detention, “criminalizing an irregular entry into a country exceeds the legitimate interest of States to control and regulate illegal immigration and leads to unnecessary detention.”180 Moreover, the United Nations Rapporteur on the human rights of migrants has sustained that “[d]etention of migrants on the ground of their irregular status should under no circumstance be of a punitive nature.”181 In the present case, the Court considers that the objective of imposing a punitive measure upon a migrant that reenters in an irregular manner to a country after a previous deportation order cannot be considered a lawful purpose in conformity with the Convention. Need for the measure 170. In the instant case, the Court notes that the measure established in Article 67 of Decree Law 16 of 1960 was an administrative measure of a punitive nature. In this respect, the Court has already held that administrative sanctions, as well as criminal 177 Cf. Decree Law N° 16 of June 30, 1960, supra note 80. 178 The principle of legal exception provides that the right to personal liberty can only be affected by a law, which is understood, according to Article 30 of the Convention, as a general legal norm closely related to the general welfare, enacted by democratically elected legislative bodies established by the Constitution, and formulated according to the procedures set forth in the Constitutions of the States Parties for that purpose. Advisory Opinion, The Word “Laws” in Article 30 of the American Convention on Human Rights. Advisory Opinion OC-6/86 of May 9, 1986, Series A Nº 6. See also, Case of Chaparro Álvarez and Lapo Íñiguez, supra note 99, para. 56; Case of Usón Ramírez, supra note 10, para. 145, and Case of Yvon Neptune, supra note 97, para. 96. 179 Cf. Article 5 on the right to liberty and security of the European Covenant for the Protection of Human Rights and Fundamental Freedoms. 180 United Nations, “Promotion and Protection of all Human Rights, Civil, Political, Economic, Social and Cultural Rights, including the Right to Development,” Working Group on Arbitrary Detention, Group Report, A/HRC/7/4, January 10, 2008, para. 53. 181 United Nations, “Specific Groups and Individuals: Migrant Workers. Human Rights of Migrants,” Report of the Special Rapporteur, Ms. Gabriela Rodriguez Pizarro, submitted pursuant Order 2002/62 of the Human Rights Commission, E/CN.4/2003/85, December 30, 2002, para. 73 (case file of the evidence, volume V, annex 22 of the autonomous brief of pleadings, motions and evidence, folio 1993).