Mauro Floriani, the husband of Alessandra Mussolini, is one of 20 alleged clients of the teenage girls from Parioli authorities say were prostituting themselves to earn money for designer clothes and cellphones, the Italian news agency ANSA reported Tuesday.
Floriani, who was an officer in the Italian tax and border police before taking a management job for the national railway, has denied having sex with the 14- and 15-year-old girls but remains under investigation, ANSA said.
Five people have been arrested, including the mother of one of the girls.
Floriani and Mussolini, a senator with the Forza Italia party, have been married since 1989 and have three children.
The FI party is led by former Prime Minister Silvio Berlusconi, who has been mired in his own sex scandal for years.