[1] The defendant, Malchiel Gruenwald (1881–1958), a hotelier who lost 52 relatives in the Auschwitz concentration camp, had accused Rudolf Kastner (1906–1957), a Hungarian lawyer and journalist who became a civil servant in Israel in 1947, of collaborating with the Nazis in Hungary during the Holocaust.

Gruenwald was represented by Shmuel Tamir (1923–1987), a former Irgun commander, who turned the case into one that examined the actions of the governing Zionist Mapai party during the Holocaust, and what had been done to help Europe's Jews.

They alleged that he had known about the gas chambers since at least the end of April 1944 – when he had received a copy of the Vrba-Wetzler report – but had neglected to inform the wider community that they were not being deported from Hungary to be "resettled," as the Nazis had said.

The five judges, Chief Justice Yitzhak Olshan, Shimon Agranat, Moshe Silberg, Shneur Zalman Cheshin, and David Goitein, upheld the appeal on the charge that Kastner was guilty of the indirect murder of Hungarian Jews.

According to Asher Maoz, Silberg agreed with the trial judge that Kastner had "knowingly and in bad faith, fulfilled the wishes ... of the Nazis, and thereby made it easier for them to perform the work of mass destruction."