The national government under Reich Chancellor Franz von Papen and Reich President Paul von Hindenburg used the incident as a rationale to depose the acting government of the Free State of Prussia by means of an emergency decree in what came to be known as the Prussian coup d'état of 20 July 1932.

[1] In Schleswig-Holstein, to which Altona belonged, two Social Democrats and two Communists were killed by National Socialists in the first days of July.

Because it had a working class population that voted majority Communist or Social Democratic, it was known locally as "Red Altona" and "Little Moscow”.

According to their own statements, they drove people off the street, shouted out orders to close windows, and shot at alleged attackers and those shooting from rooftops.

Thanks to the French resistance fighter Léon Schirmann, who re-evaluated the files on the Altona Bloody Sunday in 1992, it is now known that the fatal bullets had in fact come from police pistols.

[6] Three days later, on 20 July 1932, Reich Chancellor Franz von Papen used the events in Altona as a rationale for the Prussian Coup d'état (Preußenschlag), in which the Prussian minority government that had resigned but was still acting in a caretaker capacity was deposed and the democratic constitution of the Free State of Prussia suspended.

After the National Socialists seized power, the Nazi state’s judiciary opened the so-called Bloody Sunday Trials.

[9] In the first trial, from 8 May to 2 June 1933, four of the defendants, Bruno Tesch, Walter Möller, Karl Wolff, and August Lütgens, who were classified as Communists, were sentenced to death by the Special Branch of the Altona District Court which had been set up by National Socialist judicial politicians.

Schirmann had discovered that there had been no shooting from roofs or upper floors, that no Communist gunmen had been arrested, and that no weapons had been found during house searches.

[14] In November 1992 the court acknowledged the falsification of evidence in the trials and overturned the death sentences against the four alleged perpetrators.