The documents were handed over basing on the instructions of the Prosecutor of the Warsaw Branch Commission for the Prosecutions of Crimes against the Polish Nation on dissemination and release of the proceeding’s records of the case No. S 38/04/Zk related to the Katyń Massacre i.e. crime according to article 118 § 1 of criminal code and others. On 8 April 2011 the President of the Institute of National Remembrance – Commission for the Prosecutions of Crimes against the Polish Nation handed over digital copies of 20 volumes of authenticated copies of the documents of the investigation No. 159 on Katyń Massacre carried out by the Chief Military Prosecutor’s Office of Russian Federation to the directors of the Central Military Achieves and the Central Archives of Modern Records.