Berlusconi's support ensured the survival — for now — of Letta's 5-month-old left-right coalition. But it signalled that the 77-year-old billionaire's once unchallenged authority over Italy's centre-right has wobbled as his judicial woes catch up with him.
"Italy needs a government that can produce structural and institutional reforms that the country needs to modernize," Berlusconi said in his brief remarks. "We have decided, not without internal strife, to vote in confidence."
It was a major setback for Berlusconi, who over the weekend had demanded his five Cabinet ministers quit the government and bring it down, incensed at a vote planned Friday that could strip him of his Senate seat following his tax fraud conviction and four-year prison sentence.
But in a remarkable challenge to Berlusconi's authority, several allies balked and said they would instead support Letta's hybrid coalition to push ahead with necessary economic and political measures. Italy is in its second year of recession, youth unemployment reached a record 40 per cent last month and Italy's president has insisted that a new electoral law be passed to avoid inconclusive results in any future general election.
The unusual show of defiance could signal that Berlusconi's influence has seriously eroded after two decades leading Italy's centre-right and being the main protagonist in Italy's political scene. Some commentators have likened Berlusconi's erratic and seemingly counterproductive reaction to the challenge to the desperate, fitful sparks of a candle going out.
But Berlusconi has endured numerous political setbacks in the past, only to re-emerge strong. For the first time ever, though, Berlusconi now has a definitive court sentence against him and the very real possibility that he could be barred from holding public office.
Berlusconi's close collaborator Renato Schifani insisted that Berlusconi hadn't been weakened and stressed that the party had voted together.
"I am truly happy that there was no split," he was quoted as saying by Italian news agencies. "Berlusconi's leadership has been strengthened."
Heading into the confidence vote, the numbers were in flux. Dissenting Sen. Roberto Formigoni said some 25 Berlusconi allies had defected and signed on to support Letta, apparently enough to tip the balance in Letta's favour in the 321-member chamber.
Rather than highlight the divisions and defections, Berlusconi instead threw in the towel and changed course. In the end, the Senate voted to back Letta 235-70 with 14 abstentions and one absence.
The Milan stock exchange gained nearly 2 per cent on the announcement, which seemed to have caught the entire chamber by surprise since minutes earlier a party leader had said Berlusconi's forces would vote against Letta.
In a speech to the Senate, Letta hailed his 5-month-old government's successes and outlined his agenda to revive Italy's moribund economy and turn around its record unemployment. He warned lawmakers that Italy "runs a risk, a fatal risk" depending on the choices they make.
"Give us your confidence to realize these objectives. Give us your confidence for all that has been accomplished," Letta said to applause. "A confidence vote that isn't against anyone, but a confidence vote for Italy and Italians."
Berlusconi's People of Freedom party has been badly divided ever since Italy's high court upheld his tax fraud conviction and sentence in August. But it has been thrown into chaos after several lawmakers and his closest ally and political heir Angelino Alfano openly defied him and said they would support Letta.
Alfano has served as Letta's deputy in the hybrid government and clearly thinks it has accomplished a good deal of the Berlusconi party agenda.
With Alfano sitting by his side, Letta appealed to lawmakers' sense of duty to not create any more upheaval, which has caused Italy untold financial loss in recent years. He compared it to Italy's great post-World War II economic boom that was accompanied by comparative political stability.
"The majority of Italians are telling us — I should say they are yelling at us — that they can't take any more of these scenes of bloodshed in the political arena, and (politicians) who fight over everything but nothing ever changes," he said.
Many centre-left lawmakers, as well as ordinary Italians, have expressed disgust that the government was essentially teetering over the legal woes of a single man, since the crisis began over Berlusconi's attempt to avoid being kicked out of the Senate for his tax fraud conviction.
A law passed in 2012 says anyone receiving sentences longer than two years cannot hold public office for six years. Berlusconi has challenged the law's constitutionality and has accused judges who handed down the sentence of trying to eliminate him from Italy's political life.
Letta addressed his claims straight on in his speech to the Senate, saying Italy is a country based on the rule of law.
"In a democratic state, sentences are respected and applied, always with the right to the defence without treatment in favour or against individuals, whether they be citizens or senators," he said.
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