Political Police in the Second Polish Republic was a secret, specialised service assigned mainly to surveying the whole of political and social life in the country and to chasing perpetrators of anti-state crimes, especially the people suspected of revolutionary activity. In the period discussed, it was completely reorganised four times and it appeared under different names: Political Defence, Information Service, Political Police and Investigation Service with specialised departments to fight against political crimes. In practice, Political Police used methods defined as investigational, e.g. arrests, temporary custody, search of people and property, questioning, chases; and operational ones, e.g. observation, surveillance, tapping or confidential enquiry.Till 1926 political services in Lublin Voivodeship were particularly interested in social and political organisations, the activity of which posed a threat to the legal order and the social arrangement of the state at that time. Full operational surveillance was carried out with respect to parties and political movements of communist nature, national minorities and radical peasant activists, whereas the parties that wanted to keep the bourgeois order were not of particular interest to political counterintelligence, but they were only under discrete operational surveillance.After the May Coup, the range of interests of information services in the fourth district changed substantially. In addition to the activity of communists and national minorities representatives, it encompassed the whole legal Pilsudski opposition.Political Police in Lublin Voivodeship had a very important role in internal politics. It worked among other things on:• exposing social tensions, anti-government atmosphere, revolutionary and anti-state actions (mainly communists and nationalists of national minorities);•observing legal groups and political parties as well as trade unions and parliament representatives.Escalation of political crimes in Lublin district was the largest in those regions where illegal communist organisations, Ukrainian national minorities (poviats: Hrubieszowski, Tomaszowski Chelmski and Wlodawski) and Jewish national minorities (poviats: Chelmski, Siedlecki, Wlodawski, and Grodzki Lubelski) were active.Accusations of communist activity were mainly made against people of Jewish nationality and somewhat less frequently against those of Ukrainian, Belarusian or Polish nationalities.