4 STATISTICAL OVERVIEW OF THE STATELESS POPULATION IN THE CZECH REPUBLIC In official national statistics, stateless persons are recorded as foreigners as defined in the Aliens Act. The data on foreigners are gathered by the authorities only up until Czech nationality is granted. The data concerning stateless persons in the Czech Republic presented below77 are based on statistical records taken from the publicly available governmental sources described below. The Czech Republic lacks one central register containing all information on foreign nationals living in the Czech Republic. Basic and most up-to-date data are provided by the MoI.78 Summary statistics on the number of foreign nationals are also regularly published by the Czech Statistical Office (CSO). CSO draws its data from the MoI and other ministries and departments in order to publish them in the cross-sectional statistical report entitled “Foreigners”.79 The population census represents another important source of statistical data. Extracting and compiling relevant data from several registers that primarily serve the needs of individual ministries has proven problematic. In some cases, the numbers of foreign nationals differ across various sources (registers) even where the definition is identical.80 Moreover, these statistics only provide information on foreign nationals regularly staying in the Czech Republic, i.e. who have a certain type of residence permit. Some information about persons irregularly staying in the Czech Republic can be derived from annual status reports on migration and integration of foreigners in the Czech Republic81 published by the MoI. However, its scope is confined to detected irregular migrants which represents only a small part of the overall scope of irregular migration. A more complete picture of irregular migration remains estimated by specialised surveys and expert opinions.82 24 77 Their visualisations have been produced by the authors of this study. 78 The Ministry maintains two main registers, i.e. the Foreigner Information System (FIS) and the Population Register Information System (PRIS) [in Czech: Cizinecký informační systém (CIS) and Informační systém evidence osob (ISEO)]. 79 ČSÚ, Průřezová statistika Cizinci [Cross-sectional Statistics “Foreigners”(CSO)], Czech Statistical Office [online], 2018, available at: https://www.czso.cz/csu/cizinci/cizinci-pocet-cizincu. 80 Y. Leontiyeva, D. Chytil, Statistiky a výzkumy imigrantů aneb jak srovnávat nesrovnatelné [Statistics and Surveys of Immigrants: Comparing the Incomparable], in J. Krejčí, Y. Leontiyeva (eds.) Cesty k datům. Zdroje a management sociálněvědních dat v České republice [Road to Data: Sources and Management of Social Science Data in the Czech Republic], Prague: Sociologické nakladatelství SLON, 2012, p. 352 (in Czech). 81 According to the report, 4,738 irregular migrants were detected in 2017, representing a decrease of 9.9% compared to 2016. 82 ČSÚ, Koncepce výběru a zpracování statistických údajů [Concept of Collecting and Processing of Statistical Data] op. cit. D. Topinka, Uvíznuti v nelegalitě [Trapped in Illegality], Sociální studia [Social Studies], 3 (1), 2006, pp. 73–88 (in Czech). Faces of Statelessness in the Czech Republic