Alvaro Hernandez, a 40-year-old convicted burglar, is seeking unspecified damages for injuries allegedly sustained when Brancato beat him up for not getting off the phone fast enough last January at the now-closed Oneida Correctional Facility in Rome, N.Y., the New York Post reported.
"[Hernandez] was just talking to his wife and minding his own business, and it was a brutal assault, sudden and painful. From what I understand, this is in keeping with Lillo's character, which is very violent," Eric Schneider, Hernandez' lawyer, told the newspaper.
The actor lost phone and commissary privileges, and was confined to his cell for 23 hours a day for a month after an investigation into Hernandez' complaint.
Brancato was transferred to the state prison in Hudson and Hernandez to the facility in Coxsackie when the Oneida jail closed.
"He thinks he runs the place, like he's God's gift to this earth. He tells me: 'Hang up the phone! I gotta use the phone!'" Hernandez told the Post at the time of the attack. "He forces open the door and spits at me, and he's punching me in the face and on the head."
Brancato, 35, starred in the film "A Bronx Tale" and had a recurring role on TV's "The Sopranos."
He is serving a 10-year prison sentence for a 2005 burglary, which resulted in the death of an off-duty police officer. Brancato will be eligible for parole in 2014.