INTRODUCTION Country backgrounds The systems have several aspects in common: the deprivation of liberty of persons with psychosocial and intellectual disabilities is based on the suspects assumed 'dangerousness' (i.e., dangerousness and risk of harming themselves or/and others) and with the aim of providing adequate treatment to reduce this ‘dangerousness’, often without a set time limit. To assess progress, persons concerned are heard ex officio by a court on an annual or biannual basis. In Austria, preventive custodial measures may be imposed on persons because of their ‘dangerousness’ if they are not held criminally responsible for their offence. Instead, if a person with intellectual or psychosocial disabilities is held criminally responsible, they are subjected to preventive detention for parts of, instead of or after the prison sentence if still considered ‘dangerous’.21 A person can be held in a specialised detention facility, a designated part of a prison or the forensic-psychiatric department of a hospital – in all cases for an unset time.22 In Germany, persons exempted, partly exempted and/or, in case of addiction, not exempted from criminal liability are detained until they are no longer considered ‘dangerous’. They are either held in clinics for forensic psychiatry or withdrawal centres. The latter accommodates persons with (substance) addictions, who are forced to undergo treatment in addition to their prison sentence for a set time. Finally, if held criminally responsible or partly exempted from criminal liability, persons with intellectual and psychosocial disabilities can be detained in an institution for preventive detention annexed to a regular prison in addition to their sentence without time limits.23 In Italy, persons with psychosocial and intellectual disabilities with no or diminished criminal responsibility, if considered to be ‘dangerous’, are accommodated either in extra-mural support programmes or in Residences for the Execution of Security Measures (REMs). Since 2014, the preventive custodial measures in REMs cannot exceed the length of the maximum sentence foreseen for the offence committed. Persons with pre-existing psychosocial disabilities who are criminally responsible are placed in prisons serving a prison sentence. Since April 2019, detainees who are criminally responsible with a supervening or pre-existing mental condition that is incompatible with prison can serve their sentence in home detention or in a healthcare facility (never in REMs) depending on their therapeutic needs.24 3