On April 13, 1990, the Soviet press agency TASS officially announced that the Soviet government “took on responsibility for the crimes committed in the forests of Katyn by Beria, Merkulov, and their accomplices," and called it one of “the most grievous crimes of Stalinism."
The term “Katyn tragedy” refers to the mass execution of about 14, 000 Polish officers and soldiers in April-May of 1940 in the Katyn forests.
The issue has been a fierce controversy ever since April 13, 1943, when German troops reported a huge grave site near the Russian city of Smolensk. The Soviet party issued an official refutation, saying the Polish convicts, occupied at the local construction camp, were captured by the German fascists and executed.
A special committee formed by the Soviet government opened on January 12, 1944, and presented a number of trumped-up 'proofs' of the German involvement in the Katyn massacre. Moreover, in 1945-1946, at the Nurnberg International Military Tribunal against the major Nazi criminals, the Soviet party tried to include the Katyn tragedy on the list of charges against the Germans. The Tribunal, however, wasn’t convinced with the evidence and testimony proposed by the Soviet party, and abstained from putting the Katyn atrocity on the Nazi rap sheet.
In December of 1952, a report was filed by a special committee of the US Congress, stating that the “People’s Commissariat for Interior Affairs was responsible for mass killings of the Polish soldiers, workers, and intelligentsia, in the Katyn forest near Smolensk."
The statement was based on the close inspection of the relevant papers and interrogation of the witnesses.
Ever since, the Soviet Union had made multiple efforts to pawn the terrifying military crime off on the Germans; half a century passed until the truth was finally admitted.
In 1990, the Main Military Procuracy filed several law suits after remains of bodies had been discovered. It charged Stalin and other members of the Politburo, who had signed the document dated March 5, 1940, which propelled the execution. After the proof had been found that Polish soldiers and officers had been murdered for political reasons, the victims were fully exonerated, as were citizens of the Western regions of Ukraine and Belarus, also found among the Katyn victims.
In March 2005, however, the military Prosecutor General suddenly announced the closing of the “Katyn case," and the list of the perpetrators was labeled as “top secret." According to the prosecutor, the case still contained too much confidential information to go any further with the investigation. Even Poland was only allowed to see 67 volumes of the hearing, as another 116 still had state secrets in them.
The 13th of April was officially proclaimed worldwide as “Katyn Memorial Day”.