- 22 e. information on rights 44. The CPT has already stressed the importance which it attaches to people detained by the police being expressly informed without delay of all their rights (see paragraph 35 above), including those referred to in paragraphs 36 to 43 above. In order to ensure that full information on rights is provided, the CPT recommends that a form setting out those rights be given systematically to persons detained by the police at the outset of their custody. The form should be available in different languages. The person concerned should also certify that he has been informed of his rights. f. conduct of interrogations 45. Police officers met by the delegation stated that they had no precise directives on how to conduct interrogations (though certain officers indicated that they had received training in interrogation methods at the Police Academy). However, reference was made to Article 137, paragraphs a. to d., of the Penal Code (cf. paragraph 16). 46. The art of questioning criminal suspects will no doubt always be based in large measure on experience. Nevertheless, the CPT considers it essential for the very general provisions contained in Article 137, paragraphs a. to d., of the Penal Code to be supplemented by a formal code of conduct for interrogations setting out in detail the procedure to be followed on a number of specific points. The existence of such a code would inter alia help to underpin the lessons taught during police training. The code should deal inter alia with the following: the systematic informing of the detainee of the identity (name and/or number) of those present at the interrogation; the permissible length of an interrogation; rest periods between interrogations and breaks during an interrogation; places in which interrogations may take place; whether the detainee may be required to remain standing while being interrogated; the interrogation of persons who are under the influence of drugs, alcohol, medicine, or who are in a state of shock. It should also be required that a record be systematically kept of the time at which interrogations start and end, of the persons present during each interrogation and of any request made by the detainee during the interrogation. The position of specially vulnerable persons (for example, the young, those who are mentally disabled or mentally ill) should be the subject of specific safeguards. The CPT recommends that such a code of conduct for interrogations be drawn up for the Greek police force.