Italy's top court was set to begin reviewing Tuesday a law shielding Prime Minister Silvio Berlusconi from prosecution, potentially posing deeper troubles for the scandal-hit leader, AFP reported.
Criminal cases involving the billionaire media mogul could become active if the court's 15 judges decide the law pushed through shortly after Berlusconi returned to power last year is unconstitutional.
They include one in which he is suspected of having paid 600,000 euros (875,000 dollars) to his former tax lawyer, David Mills of Britain, in return for false testimony in two trials in the 1990s.
While Berlusconi, 73, has been dogged by a string of scandals involving his private life, some analysts say a Constitutional Court decision that strips his immunity could cause the worst damage.
"The risk is that the shadow of a conviction weighs far heavier than his sexual escapades, which have mostly made his voters laugh," said Marco Tarchi, political science professor in Florence.
The law the court will examine was adopted in July 2008, six weeks after Berlusconi returned for a third term as prime minister.
It grants immunity to the holders of Italy's four top political jobs -- prime minister, president and the speakers of the two houses of parliament -- while they are in office.
Opposition politicians have harshly criticised the law.
Berlusconi has been besieged by scandals, notably over his attendance at the 18th birthday party of an aspiring model which led his wife to seek a divorce.
But the flamboyant leader holds a comfortable majority in parliament thanks to his alliance with the anti-immigration Northern League party.
Berlusconi is alleged to have bribed Mills, a consultant on offshore tax havens, to provide false evidence at two earlier trials in the late 1990s.
Mills was sentenced in February to four-and-a-half years in jail.
The prime minister has denied paying a bribe and repeatedly accused magistrates, notably in his native Milan, of conducting a politically motivated campaign against him.
Mills and Berlusconi, along with a dozen other defendants, have also been accused of tax fraud in the purchase of film rights in the United States by Mediaset, the television group owned by the Berlusconi family.
Mills was tried separately in the case since Berlusconi is shielded from prosecution.
Berlusconi's battles with the law have marked his public life since he burst onto the political scene in the mid-1990s.
He has faced charges including corruption, tax fraud, false accounting and illegally financing political parties.
Although some initial judgments have gone against him he has never been definitively convicted.
It is unclear when the Constitutional Court could issue its decision, which will be based on a court file containing seven volumes and 3,218 pages.