Preventing Torture An Operational Guide for National Human Rights Institutions - Updated Edition and others). The memorandum of understanding should explicitly guarantee the NHRI the powers it needs for effective monitoring (see above). In particular, it should include the guarantee of unrestricted access at any time and the ability to conduct interviews in private with persons deprived of liberty selected by the monitoring team. 1.2. Establishing a programme of visits In establishing a programme of visits, NHRIs should first prepare a list all types of places of detention that should be visited. The list should include the type of facility (prison, pre-trial detention facility, etc.), its holding capacity (official and actual) and its location. Ideally, NHRIs should visit all places where people are, or may be, deprived of their liberty: prisons, police stations, mental health institutions, juvenile detention facilities, military facilities, immigration detention centres and others. After compiling this initial list, NHRIs then need to select the places of detention that they intend to visit, on the basis of selection criteria they have identified in advance, such as: • a cross-selection of different categories of facilities by region or at the national level • complaints received (or lack of complaints) or known human rights problems • high levels of risks, for example the first hours of detention • the existence of other monitoring mechanisms • the situations of vulnerability of persons deprived of liberty • remote locations. The programme of visits will also depend on the type and length of the visits that the NHRI intends to conduct. Ideally, NHRIs should undertake a combination of in-depth visits, that last several days and analyse all aspects of conditions and treatment in a facility, and short visits that provide a general overview of the detention situation as well as thematic and follow up visits. NHRIs may find that announcing their visits, especially in case of in-depth visits to large establishments, may facilitate the conduct and overall dialogue with the authorities. Some visits, however, should usually be unannounced, in particular visits to police stations, where the risk of ill-treatment is usually greater than in other custodial settings. The “surprise effect” is also particularly relevant, as detainees may be at risk of being removed, hidden or transferred prior to the visit if it is announced. As part of a regular monitoring programme, it is important to determine how regularly different places of detention will be visited. Ideally, places of detention should be visited once a year and those facilities that present higher risks should be visited more frequently. It is also necessary that programmes of visits take into account the required time for the preparation, in particular when new areas or issues are to be monitored, as well as capacities, resources and expertise needed. 1.3. Developing practical tools and training NHRIs may decide to develop practical tools to assist them undertake visits, such as checklists or questionnaires for interviews. These tools can help ensure that a consistent approach is used during each visit to places of detention, especially when there are different monitoring teams from the NHRI. They should, however, provide a general guide for the visit, rather than setting out a format to be strictly followed. Monitoring places of detention requires the ability to adapt to a variety of situations and to respond to the specific circumstances of particular detention facilities. 1.4. Preparing for the visit It is crucial that NHRIs set aside adequate time to prepare for the visit, as this ensures that the monitoring team can make greatest use of the time they spend in the detention facility. 112