Italian businessman Libero Grassi was killed by the Sicilian Mafia in Palermo after taking a public stand against their extortion demands.

Libero Grassi was an Italian clothing manufacturer from Palermo, Sicily, who was killed by the Mafia after taking a solitary stand against their extortion demands. The businessman wrote an open letter to the local newspaper informing the extortionists that he was no longer willing to pay pizzo, a Sicilian term for protection money. Other business-owners and shopkeepers in Palermo refused to join his public campaign. Grassi was gunned down in the street near his home eight months after writing the letter.

The Sicilian Mafia or Cosa Nostra, also simply referred to as Mafia, is a criminal society and criminal organization originating on the island of Sicily and dates back to the mid-19th century. Emerging as a form of local protection and control over land and agriculture, the Mafia gradually evolved into a powerful criminal network. By the mid-20th century, it had infiltrated politics, construction, and finance, later expanding into drug trafficking, money laundering, and other crimes. At its core, the Mafia engages in protection racketeering, arbitrating disputes between criminals, and organizing and overseeing illegal agreements and transactions.

Palermo is a city in southern Italy, the capital of both the autonomous region of Sicily and the Metropolitan City of Palermo, the city's surrounding metropolitan province. The city is noted for its history, culture, architecture and gastronomy, playing an important role throughout much of its existence; it is over 2,700 years old. Palermo is in the northwest of the island of Sicily, by the Gulf of Palermo in the Tyrrhenian Sea.

The pizzo is protection money paid to the Mafia often in the form of a forced transfer of money resulting from extortion. The term is derived from the Sicilian pizzu ('beak'). To "let someone wet their beak" is to pay protection money. The practice used to be widespread in Southern Italy, not only by the Sicilian Cosa Nostra but also by the 'Ndrangheta in Calabria and the Camorra in Campania. Another etymological explanation of the term is "beakerful", referring to the right of an overseer to scoop from the grain being threshed by peasants.