He was the son of Bernardo Mattarella, a member of Christian Democracy (DC), and a leading political boss in Sicily in the 1950s.

Inspired by the politics of Giorgio La Pira, he adhered to the more progressive approach of national leader Aldo Moro.

[3] Initially believed to be an act of neo-fascist terrorism, his assassination was spurred by his strong commitment against the relationships of numerous Sicilian politicians (mostly members of DC itself) with the Mafia.

Andreotti and Lima allegedly arrived at the meeting in a bullet-proof Alfa Romeo, belonging to the Salvo cousins.

[2] According to Marino Mannoia the killers of Mattarella were Salvatore Federico, Francesco Davì, Santo Inzerillo and Antonio Rotolo, while the principals were on the Sicilian Mafia Commission, at the time – Bontade and Inzerillo, as well as Michele Greco, Salvatore Riina, Bernardo Provenzano, Antonino Geraci, Francesco Madonia, Pippo Calò, Bernardo Brusca.

The judges decided to uphold Andreotti's original acquittal on grounds of expiration of statutory terms because he had severed relations with the Mafia from 1980.

[13] The Italian national Anti-mafia Prosecutor, Piero Grasso, said that Mattarella was killed because "he was trying to accomplish a new political and administrative project, a true revolution, which, through a deep change in the management of the Region, aimed at breaking well established relations between bureaucracy, politics, business and the mafia.