In January 1958, Oswald Pirow was appointed to prosecute the case, and in February the judge ruled that there was "sufficient reason" for the defendants to go on trial in the Transvaal Supreme Court.[94] The formal Treason Trial began in Pretoria in August 1958, with the defendants successfully applying to have the three judges - all linked to the governing National Party - replaced.
NgoJanuwari ka 1958, u-Oswald Pirow waqokwa ukuba ngumshushisi wecala, kwathi ngoFebruwari, ijaji lanquma ukuthi kunobufakazi obenele lokuthi abamangalelwa ukuthi bayiswe eNkantolo eNkulu ye-Transvaal Supreme Court.[102] Icala labo le-Treason Trial laqala ngokomthetho ePretoria ngo-Agast 1958, kanti abamangalelwa benza isicelo sokuthi amajaji amathathu asuswe esikhundleni sawo kungene amanye ngoba onke ayexhumane ne-National Party.