On this day in 1925, twelve organizers with the Communist Party of Great Britain (CPGB) were arrested and charged with violating the Mutiny Act of 1797. Six served time in prison after refusing to renounce communism.

The names of the twelve arrested were John Ross Campbell, Jack Murphy, Wal Hannington, Ernie Cant, Tom Wintringham, Harry Pollitt, Hubert Inkpin, Arthur McManus, William Rust, Robin Page Arnot, William Gallacher, and Tom Bell.

Many of those arrested were Party leaders. The CPGB elected to be silent on the arrests, for fear of the next set of leaders being arrested like the first.

The arrested communists were subjected to a highly politicized trial that lasted for eight days. Five of the group were sentenced to a year in prison for "members of an illegal party carrying on illegal work in this country".

To the remaining seven, the conservative judge offered an ultimatum: "Those of you who will promise me that you will have nothing more to do with this association or the doctrine it preaches, I will bind over to be of good behaviour in the future. Those of you who do not promise will go to prison." All but one refused.