He was one of the national leaders of the Fasci Siciliani (Sicilian Leagues) a popular movement of democratic and socialist inspiration from 1891 to 1894.

Together with the anarchist Giovanni Noè,[1] he set up the first Fascio dei Lavoratori in Messina on 18 March 1889, but the organisation remained dormant after the arrest of Petrina in July of that year.

[2] Petrina was among the 500 delegates from nearly 90 leagues and socialist circles at the Congress of the Fasci that was held in Palermo on 21–22 May 1893.

[2] In July 1893, he was elected in the municipal council of Messina, where he immediately discovered serious abuses that had been committed in the City Hall for years.

[4] Following the repression of the Fasci Siciliani by the government of Francesco Crispi, he was arrested on 4 January 1894, and was brought to trial.