9 (3) Except in special circumstances, staff performing duties which bring them into direct contact with prisoners should not be armed. Furthermore, staff should in no circumstances be provided with arms unless they have been trained in their use. Inspection 55. There shall be a regular inspection of penal institutions and services by qualified and experienced inspectors appointed by a competent authority. Their task shall be in particular to ensure that these institutions are administered in accordance with existing laws and regulations and with a view to bringing about the objectives of penal and correctional services. Part II RULES APPLICABLE TO SPECIAL CATEGORIES A. Prisoners under sentence Guiding principles 56. The guiding principles hereafter are intended to show the spirit in which penal institutions should be administered and the purposes at which they should aim, in accordance with the declaration made under Preliminary Observation 1 of the present text. 57. Imprisonment and other measures which result in cutting off an offender from the outside world are afflictive by the very fact of taking from the person the right of self-determination by depriving him of his liberty. Therefore the prison system shall not, except as incidental to justifiable segregation or the maintenance of discipline, aggravate the suffering inherent in such a situation. 58. The purpose and justification of a sentence of imprisonment or a similar measure deprivative of liberty is ultimately to protect society against crime. This end can only be achieved if the period of imprisonment is used to ensure, so far as possible, that upon his return to society the offender is not only willing but able to lead a law-abiding and self-supporting life. 59. To this end, the institution should utilize all the remedial, educational, moral, spiritual and other forces and forms of assistance which are appropriate and available, and should seek to apply them according to the individual treatment needs of the prisoners. 60. (1) The regime of the institution should seek to minimize any differences between prison life and life at liberty which tend to lessen the responsibility of the prisoners or the respect due to their dignity as human beings. (2) Before the completion of the sentence, it is desirable that the necessary steps be taken to ensure for the prisoner a gradual return to life in society. This aim may be achieved, depending on the case, by a pre-release regime organized in the same institution or in another appropriate institution, or by release on trial under some kind of supervision which must not be entrusted to the police but should be combined with effective social aid. 61. The treatment of prisoners should emphasize not their exclusion from the community, but their continuing part in it. Community agencies should, therefore, be enlisted wherever possible to assist the staff of the institution in the task of social rehabilitation of the prisoners. There should be in connection with every institution social workers charged with the duty of maintaining and improving all desirable relations of a prisoner with his family and with valuable social agencies. Steps should be taken to safeguard, to the maximum extent compatible with the law and the sentence, the rights relating to civil interests, social security rights and other social benefits of prisoners.