6 15. In its 1st General Report (op. cit. paragraphs 74 to 77), the CPT drew attention to certain legal issues which had arisen concerning the interpretation of the Convention i.e. the application of visa requirements to members of CPT visiting delegations, the giving of reasons when Article 14 (3) of the Convention is invoked (objections to an expert, or other person assisting the Committee, taking part in a visit), and the legal status of the Explanatory Report on the Convention. These different questions were subsequently the subject of a report drawn up by the Ministers Deputies' Rapporteur Group on Legal Co-operation, which was forwarded to the CPT by the Committee of Ministers. The views expressed by the Rapporteur Group were not entirely in line with those advanced (and still held) by the CPT. Nevertheless, a modus vivendi has now been reached which, for the present, should make it possible to resolve satisfactorily any difficulties that might arise in relation to the questions of visa requirements and the application of Article 14 (3) of the Convention. 16. The CPT wishes to take this opportunity to raise the question of the expiry dates of its members' terms of office. As is clear from Appendix 2 A, there are already several different expiry dates, and the situation will inevitably become more complicated as new members join the Committee as a result either of further ratifications of the Convention or of existing members not completing their terms of office. In due course, the multiplicity of expiry dates could cause significant organisational difficulties. Consequently, the CPT believes that consideration might usefully be given to drawing up a Protocol to the Convention containing provisions similar to those found in Article 22, paragraph 3, of the European Convention on Human Rights, the aim being to place each member in one of two groups, thereby ensuring an orderly renewal of one half of the Committee's membership every two years. The CPT would like to be consulted at an appropriate stage during the drafting of such a Protocol. c. Visits in 1991 17. As already indicated, the CPT carried out five periodic visits in 1991: in chronological order, to Spain (1 to 12 April 1991), Sweden (5 to 14 May 1991), Switzerland (21 to 29 July 1991), France (27 October to 8 November 1991) and Germany (8 to 20 December 1991). In accordance with the Committee's current practice, these countries were chosen by lot. The CPT had planned to carry out a sixth periodic visit, to Portugal, during 1991. However, due to workload difficulties within the Secretariat, it was decided to postpone the visit to 19924. In addition, the CPT decided to carry out a second ad hoc visit to Turkey. This visit took place from 29 September to 7 October 1991 (the Committee's first visit to Turkey was carried out from 9 to 21 September 1990). 4 The visit to Portugal took place from 19 to 27 January 1992.