The quaesitor (Greek: κοιαισίτωρ, κυαισίτωρ) was a Late Roman/Byzantine police official of Constantinople, specifically a magistrate, responsible for controlling the flow of legal and illegal immigration into the capital city of Byzantium.^[1] The office of the quaesitor was first established in 539 through the Novella 80 of Emperor Justinian I (r. 527–565), designed to deal with the arrival of unemployed people to Constantinople living as criminals or beggars.^[1] One of his functions was to investigate people passing through Constantinople by determining their names, origins, and reasons for being in the city.^[1] Furthermore, the quaesitor had the authority to deal with unemployed persons by forcing the physically fit among the unemployed to work in a public industry such as a bakery (if an unemployed person refused to work, he would be expelled from Constantinople).^[1] The quaesitor was also granted judicial functions whereby his court dealt with certain types of crimes such as forgery.^[2]