The trial was immediately condemned by the Holy See. All Catholics who had taken part in the court proceedings, including most of the jury members, were excommunicated by Pope Pius XII who referred to the process as the “saddest trial”
In the United States, one of Stepinac’s biggest supporters was the Archbishop of Boston, Richard Cushing, who delivered several sermons in support of him. U.S. Acting Secretary of State Dean Acheson on October 11, 1946 bemoaned the conditions in Yugoslavia and stated his regret of the trial.
Support also came from the American Jewish Committee, who put out a declaration that On October 13, 1946, The New York Times wrote that,
The trial of Archbishop Stepinac was a purely political one with the outcome determined in advance. The trial and sentence of this Croatian prelate are in contradiction with the Yugoslavia’s pledge that it will respect human rights and the fundamental liberties of all without reference to race, sex, language and creed. Archbishop Stepinac was sentenced and will be incarcerated as part of the campaign against his church, guilty only of being the enemy of Communism.
The National Conference of Christians and Jews at the Bronx Round Table adopted a unanimous resolution on October 13 condemning the trial:
This great churchman has been charged with being a collaborator with the Nazis. We Jews deny that. We know from his record since 1934, that he was a true friend of the Jews...This man, now the victim of a sham trial, all during the Nazi regime spoke out openly, unafraid, against the dreadful Nuremberg Laws, and his opposition to the Nazi terrorism was never relaxed.
In Britain, on 23 October 1946, Mr Richard Stokes MP declared in the House of Commons that,
[T]he archbishop was our constant ally in 1941, during the worst of the crisis, and thereafter, at a time when the Orthodox Church, which is now comme il faut with the Tito Government, was shaking hands with Mussolini....
On November 1, 1946 Winston Churchill addressed the House of Commons on the subject of the trial, expressing “great sadness” at the result.
This trial was prepared in the political sphere. It was for the purpose of dividing the Catholic Church in Croatia from its leadership at the Vatican. Tito has openly expressed this purpose....The trial was not based on justice, but was an outrage on justice. Tito’s regime has no interest in justice. It seeks only to stifle opposition....
[Stepinac] was one of the very rare men in Europe who raised his voice against the Nazis’ tyranny at a time when it was very difficult and dangerous for him to do so.
I’ll go with Winston Churchill on this one. You can go with Tito and the communists.
Credit to wiki