Are You really going to bat for the nazis here, mate?.The USSR was solely responsible for the Katyn Massacre of about 22,000 Polish military officers and intellectuals.
Despite the forensic evidence, however, the USSR denied its guilt and was fully supported in public by the USA and UK.
Even after the war, the USSR tried and convicted innocent Germans for crimes around the Katyn Massacre.
"From 28 December 1945 to 4 January 1946, a Soviet in tried seven Wehrmacht servicemen.
One of them, , who was charged with murdering numerous civilians using machine-guns in Soviet villages,
confessed to having taken part in the burial (though not the execution) of 15,000 to 20,000 Polish POWs in Katyn.
For this he was spared execution and was given 15 years of hard labor. His confession was full of absurdities, and thus
he was not used as a Soviet prosecution witness during the . He later recanted his confession, claiming
the investigators forced him to confess."
--Wikipedia
I would be hardly surprised if some extreme pro-Russian writers here still believe or wish to believe that the USSR must
be completely innocent of the Katyn Massacre and blame only the eternally convenient Nazi bogeymen for that crime.
Oh those poor poor innocent German soldiers in the east. Do You have a "mein opa" story by any chance?