16 understand that he is being detained. Second, the agent who carries out the arrest must inform him in simple language, free of technical terms, about the essential legal grounds and facts on which the arrest is based. Article 7(4) of the Convention is not satisfied by the mere mention of the legal grounds. 72. In this case, the Commission and the representatives stated that Mr. Chaparro was not informed that he was being detained and was simply told that he should accompany the police agents to make a statement. The State merely rejected these facts in general terms without providing or referring to concrete evidence. In brief, the Court has little evidence about these facts. 73. In the instant case, the victim has no available means of proving this fact. His allegation is of a negative nature, and indicates the inexistence of a fact. The State declares that the information about the reasons for the arrest was provided. This is an allegation of a positive nature and, thus, susceptible of proof. Moreover, if it is recalled that, on other occasions, the Court has established that “in proceedings on human rights violations, the defense of the State cannot be based on the impossibility of the plaintiff to provide evidence that, in many cases, cannot be obtained without the cooperation of the State,”41 this leads to the conclusion that the burden of proof on this point corresponds to the State. Consequently, the Court considers that the State has not proved that its authorities informed Mr. Chaparro of the motives and reasons for his arrest, which constitutes a violation of Article 7(4) of the Convention and, since it is also contrary to domestic law, of Article 7(2) of this treaty to the detriment of Mr. Chaparro. * * * 74. Furthermore, both the Commission and the representatives question the lawfulness of the arrest, affirming that Mr. Chaparro was not shown the respective arrest warrant. 75. This Court notes, first, that, under domestic law, there is no formal requirement that the detained person must be shown the actual court order. Accordingly, there cannot be unlawfulness in the terms of Article 7(2) of the Convention. 76. Second, the first obligation of Article 7(4) of the Convention does not specify that the information that the detained person should receive must be in writing. The Court considers that this obligation can be complied with orally; however, this is not the case of the second obligation of Article 7(4) of the Convention regarding prompt notification of the charge or charges against him, which must be given in writing. Nevertheless, in the instant case, it is not necessary to examine the second obligation of Article 7(4) of the Convention because, as established in paragraph 73 above, the State failed to comply with the first obligation of this Article. * * * 77. In the case of Mr. Lapo, the Court finds it unnecessary to examine whether he was informed of the purpose and reasons for his arrest, since it has been decided that the arrest itself was unlawful (supra para. 66) in clear violation of Article 7(2) of the Convention. 41 Case of Velásquez Rodríguez, supra note 20, para. 135; Case of Zambrano Vélez et al., supra note 13, para. 108, and Case of the Yakye Axa Indigenous Community, supra note 12, para. 16.