Lustration in Poland refers to the policy of limiting the participation of former communists, and especially informants of the communist secret police (from the years 1944–90), in the successor governments or even in civil service positions. Lustration, "cleansing", derives from Latin lustratio, a Roman purification ceremony. The first lustration bill was passed by the Polish Parliament already in 1992, but it was declared unconstitutional by the Constitutional Tribunal of the Republic of Poland. Several other projects were then submitted and reviewed by a dedicated commission, resulting in a new lustration law passed in 1996.
In the years 1997–2007 lustration was dealt with by the office of Public Interest Spokesperson (Rzecznik Interesu Publicznego), who analyzed lustration declarations and could initiate further proceedings, including submitting a request to the courts to initiate a legal lustration proceeding. The declarations may be seen as forms of public confessions, through which offices are exchanged for truth in a similar way as amnesty was exchanged for truth in South Africa. Owing to its resemblance with the South African truth and reconciliation process, the Polish lustration system of the period is seen as the most innovative among all lustration models in Central and Eastern Europe.
On 18 December 2006 Polish law regulating Institute of National Remembrance (pol. Instytut Pamięci Narodowej - IPN) was changed and came into effect on 15 March 2007. This change gave IPN new lustration powers . The first Polish lustration laws were adopted in 1997; only since 2007 do they officially involve IPN, which has now replaced the old Polish lustration institution, the Public Interest Spokesman. According to the revised Chapter 5a of the Act of 18 December 1998 on the Institute of National Remembrance – Commission for Prosecution of Crimes against the Polish Nation (Ustawa z dnia 18 grudnia 1998 r. o Instytucie Pamięci Narodowej — Komisji Ścigania Zbrodni przeciwko Narodowi Polskiemu), the Lustration bureau of the Institute of National Remembrance performs the following functions: