ROME — A Rome court convicted dozens of defendants Thursday in a wide-ranging corruption trial that revealed a system of kickbacks and intimidation to gain control of city contracts, but acquitted all of the defendants on key charges of Mafia-style association.

The trial was the first in Italy to unite allegations of corruption with the trappings of organized crime, and the court’s across-the-board rejection of the Mafia-style allegations was a blow to prosecutors’ case, touted by Italian media as ‘‘Mafia Capital.’’

The court gave the highest sentence to the alleged ringleader, Massimo Carminati, who was handed 20 years in jail.

Just one of the 46 defendants, a gas station operator with alleged Mafia ties, was acquitted.

Prosecutors say rampant corruption, which involved the management and supply of migrant shelters, sanitation agencies, parks maintenance, and other municipal services, dated back years.

associated press