17. States must respect the right to health and ensure equal access for all persons, including prisoners or detainees, to preventive, curative and palliative health services. (…) The Special Rapporteur on the right of everyone to the enjoyment of the highest attainable standard of physical and mental health has specifically noted the link between overincarceration, overcrowding and infringements upon the right to health, especially in relation to the spread of infectious and communicable diseases, such as tuberculosis and hepatitis C. This poses risks not only to the health of other detainees, but also to the staff and even the general population once prisoners are being released.
18. Other United Nations and regional human rights bodies have also reported the negative impact of overcrowding upon the right to health of detainees through denial of, or inadequate access to, medical treatment, insufficient mental health services, lack of health-care professionals in places of detention, failure to implement effective harm-reduction programmes and drug-dependence treatment. Overcrowding has also been found to be a root cause of entirely preventable medical conditions.
42. The following phenomena have been reported as factors contributing to overincarceration and overcrowding: the failure to include time served on custodial remand in sentence calculation; the application of mandatory sentences especially for minor, non-violent crimes and severe penalties for drug-related offences; the imposition of excessively lengthy prison sentences, especially life sentences, contrary to the principle of proportionality; the absence of reasonable sentencing guidelines that would permit the reduction of excessively lengthy sentences; the lack of discretion for judges when sentencing, which prevents them from taking into consideration the individual circumstances of the detainee and the case; a great limitation to the remission of sentences; and ambiguities in the legislation that lead to unnecessary detention.
57. Proportionate sentencing is an essential requirement of an effective and fair criminal justice system. This requires that custodial sentences are imposed as measures of last resort and applied proportionately to meet a pressing societal need.
58. In order to meet the requirement of proportionality, States have been revising their penal policies and legislation in order to reduce minimum and maximum penalties, decriminalize numerous categories of petty crimes and reduce criminal sanctions for economic offences, thus contributing to reducing the total prison population. Equally, reviewing sentencing policies to reduce or eliminate mandatory minimum sentences for lesser, non-violent offences and to provide more reasonable sentencing guidelines in order to reduce excessively lengthy sentences also has had a positive effect upon the reduction of overincarceration and overcrowding. Appropriate action, including training, should be taken vis-à-vis the prosecutorial and judicial authorities with a view to eliminating unnecessary recourse to pretrial custody and modifying the sentencing practices. Special attention should be paid to the reduction of life sentences and ensuring a genuine possibility of parole for all detainees, including those serving life sentences.