Three offices of Joseon

Three Offices, or Samsa (삼사·三司), is a collective name for three government offices in Joseon Dynasty that functioned as major organ of press and provided checks and balance on the king and the officials. These were Office of Inspector General (Saheonbu·사헌부), Office of Censors (Saganwon·사간원), and Office of Special Advisors (Hongmungwan·홍문관).

While modeled after Chinese system of Censorate, they played much more prominent roles in Joseon government than their Chinese counterparts. Some historians credit Three Offices for absence of abuses by eunuchs that were prevalent throughout Chinese history.

The officials who served in these offices, called "daegan" (대간), tended to be younger and of lower rank compared to other offices such as Six Ministries but had strong academic reputation and enjoyed special privileges and great prestige. To be appointed, they went through more thorough review of character and family background. The children of officials who were impeached for corruption and children of concubines were excluded, and only those who passed literary gwageo examinations could become a daegan. As it attracted the elite of Joseon officialdom, Three Offices provided one of the fastest routes of promotion to top posts in the Royal Court and was almost a requirement to becoming a State Councillor.

It monitored government administration and officials at each level in both central and local governments for corruption, malfeasance, or inefficiency. It was also in charge of advancing public morals and Confucian customs and redressing grievances of the populace. It was headed by Inspector General (Daesaheon·대사헌), who oversaw 30 largely independent officials. It is the largest and most senior office of Three Offices.

Its chief function was to remonstrate with the king if there was wrong or improper action or policy. Important decrees of the king were first reviewed by censors, who could ask to withdraw them if judged improper. It also issued opinions about the general state of affairs. It was composed of five officials, led by Chief Censor (Daesagan·대사간).

While the primary focus for Office of Inspector General is the government officials and Office of Censors is focused on the king, two offices often performed each other's functions, and there was much overlap. Together they were called "Yangsa," (양사) which literally means "Both Offices," and often cooperated in joint actions especially when they sought to reverse the king's decision. In their role as organ of press, they did not have actual authority to decide or implement policies, but had influential voice in the ensuing debate.

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