TEIXEIRA DE CASTRO JUDGMENT OF 9 JUNE 1998 7 (a) interference by ill-treatment, assault, any other method, hypnosis or the use of cruel or deceitful means with a person's freedom to exercise his will or make decisions; ... 4. Where evidence is obtained by means that constitute a serious criminal offence under this Article, it may be used only for the purpose of prosecuting those responsible for obtaining it in that way.” Article 241 “The public prosecutor is apprised of the commission of an offence through his own investigations, by police officers responsible for investigating crime or if the offence is reported in accordance with the following provisions.” Article 242 “Even if the offender’s identity is not known, an offence must be reported to the prosecuting authorities: (a) by the police in the event of any offence which comes to their attention; ...” C. Case-law and legal theory 26. Subject to certain conditions, the Supreme Court accepts the use of “infiltrators” in the fight against drug-trafficking (judgments of 12 June 1990, BMJ no. 398, p. 282; 14 January 1993, Col. Jur. (STJ), 1993-I, p. 270; 5 May 1994, Col. Jur. (STJ), 1994-II, p. 215, delivered in the instant case; and the judgments of 22 June 1995, Col. Jur. (STJ), 1995-II, p. 238; 6 July 1995, Col. Jur. (STJ), 1995-II, p. 261; and 2 November 1995, Col. Jur. (STJ), 1995-III, p. 218). 27. Legal writers in Portugal (and in other European countries) draw a distinction, under the generic term of “infiltrators”, between an “undercover agent” and an “agent provocateur”. The former is someone who confines himself to gathering information, whereas the latter is someone who actually incites people to commit a criminal offence. In Portugal, under the law in force at the material time, legal experts regarded evidence obtained by “undercover agents” as admissible, but were more reserved about evidence obtained by “agents provocateurs” (see, for example, Costa Andrade, Sobre as proibições de prova em processo pènal, Coimbra, 1992, pp. 220 et seq., and A.G. Lourenço Martins, Droga. Prevenção e tratamento. Combate ao tráfico, Coimbra, 1984, pp. 154 et seq., and, more recently, “Droga e direito”, Aequitas, Editorial Noticias, 1994, pp. 278 et seq.).