In the late 19th century, Italy became the setting for a series of important political trials in which socialist and anarchist revolutionaries had to defend themselves against accusations of political subversion. This essay investigates the 1876 trial in Bologna that inaugurated the judicial history of the First International in Italy; the trail of 1886 against the organizers of La Boje; and the trails following the riots of the 1st of May, in Rome and in Naples. The analysis concludes with some notes on the military trials that ended in the condemnation of the organizers of the Sicilian Fasci. In each of these cases, the spectacular public portrayal of the trial and the role of the press, the courtrooms became an important place for political propaganda in which the ideas of the defendants and the arguments defense lawyers were amplified. This is demonstrated by the numerous testimones of those who joined the cause after having witnessed these trials or having been exposed to the ideals of the «sovversivi» through the press or word of mouth.