Do you have a link by any chance? The time frame is interesting.
Barton talks about this at his excellent website:
“Immediately after these elections, in which the National Socialist Party had emerged as a major force, the bishop of Mainz excommunicated all Catholic members of the party in his diocese, and banned uniformed groups entering churches ((KG 12 and A R 166)). He also gave instructions that party members would not be allowed to take an official part in funerals and other services ((RD 8, 9 and 12)). The other bishops decided to await the annual bishops’ Conferences, so as to be able to formulate a united policy. In Rome the Osservatore Romano of October 11th 1930 commented: “Belonging to the National Socialist Party of Hitler is irreconcilable with the Catholic Conscience.” In his New Year message, Cardinal Bertram of Breslau condemned extreme nationalism, without specifying the Nazi Party ((KG 13)).” KG = Die Katholiken und das Dritte Reich, by Klaus Gotto, 1990.
Robert D’Harcourt wrote:
“The German Catholic bishops have quite recently, in a series of public declarations on which the clergy have not hesitated to act, stigmatised the leaders of the National Socialist Party as traitors who should be refused the sacraments. These instructions have not been withdrawn and are still being carried out. In these circumstances the Chancellor is reluctantly compelled to remain away from the Catholic service at Potsdam. During the celebration the Chancellor and the Propaganda Minister, Dr. Goebbels, placed wreaths in the Luisenstadt cemetery in Berlin on the tomb of their murdered comrades of the Storm Troops.” ((RD 72-5)).” RD = The German Catholics, by Robert D’Harcourt, 1939.
http://www.churchinhistory.org/pages/booklets/rise(n)-1.htm