The decision to liquidate the Greek Catholic Church was one of the punitive measures that the Russian authorities introduced in the Kingdom of Poland after suppressing the January Uprising (1863-64). The ideological and political justification for this policy included such demands as redressing historical wrongs, paving the way for the return of Polonized Ruthenians to their former heritage (i.e. Russia and the Orthodox Church), and strengthening Russian elements in Poland. The gendarmerie, which served as the political police, both participated in and supervised the action against the Uniate Church. She observed and monitored an astonishingly wide range of phenomena, including: decisions of the Russian administration and their consequences, the climate of opinion among the Greek Catholic and Orthodox clergy, Uniate reactions to repression and reforms. She assessed the success or failure of official policy, the processes of changing the religious and national awareness of the population of Podlasie, and the assistance of the Roman Catholic clergy to the persecuted Uniates. The reports, recommendations and conclusions constitute an important historical source that shows the involvement of the Russian political police in the liquidation of the structure of the Greek Catholic Church, confusing and persuading the Uniates and strengthening Orthodoxy.