The publicani, referred to in primary sources as τελώναι by the Greeks and publicani by the Romans, were private contractors responsible for organizing public games, performing public duties, and providing supplies for military expeditions. Most of them were from the equites class, whose social and political status gradually increased during the Roman Republic, especially after the Second Punic War. With the informal consent of Roman officials, they formed partnerships known as societates publicanorum to increase their financial gains and securities. With the Republic acquiring more and more provinces, the government conceived a new fiscal system for lowering costs and increasing efficiency. excerpt
Tom Zhuohun Wang (Sun,) studied this question.