(CNN) -- Former Italian Prime Minister Silvio Berlusconi is facing yet another corruption charge.
A preliminary indictment by a judge in Naples alleges that the 77-year-old bribed a senator to change sides and supported his party in 2006, Berlusconi's lawyer said Wednesday.
Sen. Sergio De Gregorio's change of allegiance eventually helped bring down the center-left government of Romano Prodi in 2008, paving the way for Beruslconi to become prime minster for a third time.
The senator is cooperating with prosecutors and a first court hearing is scheduled in Naples for February 11.
Berlusconi says he is innocent, according to his lawyer, Michele Cerabona.
The former Prime Minister has been the subject of multiple corruption and bribery charges over the years.
In August, Italy's high court upheld a four-year prison sentence for tax fraud, and this month, a lower court ruled that Berlusconi should be banned from public office for two years. Because of his age, it's unlikely Berlusconi will spend any time in prison.
CNN's Hada Messia and Susanna Capelouto contributed to this report.