Former Italian Prime Minister Silvio Berlusconi was expelled Wednesday from parliament for violating an anti-corruption law, ending a 19-year tenure that spanned four recessions and did little to dent his personal popularity.

The Senate voted to strip the billionaire of his seat, Speaker Pietro Grasso said. The decision ends a three-month process begun after Berlusconi, 77, who won three general elections and spent nine years as premier, lost his final appeal of a 2012 tax-fraud conviction.

The expulsion completes the downfall of Italy's most influential politician. Berlusconi, who presented himself as a tax-cutter with the managerial talent to spur the economy, was hampered as head of government by criminal trials and squabbles within his parliamentary coalitions.

In the last two years, as a member of the ruling alliances led by Mario Monti and Enrico Letta, he supported, then criticized, austerity policies.

"Even the powerful must submit to the supremacy of the law," Sen. Loredana De Petris, of the opposition SEL party, said in a speech before the vote. "With the vote today, we want to reaffirm a principle of legality, which is the substance and the essence of democracy."

The ouster may give Letta, in his seventh month as premier, a freer hand in shaping policy. Berlusconi, who won about a quarter of the votes in a February general election, pushed Letta into a 4-billion euro ($5.4 billion) property tax cut in August.

That clout diminished over the course of the expulsion process as allies deserted him, rendering his party too small to make demands of the government.

Letta, 47, won a confidence vote in the early hours Wednesday, after a late-night Senate debate marked by the exit of Berlusconi's Forza Italia party from the coalition.

The ouster was a victory for Letta's Democratic Party, which is the biggest force in parliament and has opposed Berlusconi.

The tax-fraud conviction, which was upheld by Italy's Supreme Court on Aug. 1, is only part of the legal troubles Berlusconi faces. Under indictment on corruption charges and appealing a prostitution conviction, he is now without the immunity from arrest accorded to Italy's 951 lawmakers for the first time since 1994.

"What he's terrified of is being arrested," said James Walston, a professor at the American University in Rome. "If he loses his status as a senator, then he might just be arrested."

Berlusconi has denied all wrongdoing, saying the trials amount to political persecution. Supporters rallied in Rome on Wednesday to protest the expulsion.

Berlusconi, who amassed a fortune of $8.2 billion through real estate and media investments, oversaw two recessions in his second stint as premier, from 2001 to 2006.

A third contraction took hold from 2008 to 2009, during Berlusconi's last mandate, which ended in his November 2011 resignation at the advent of the debt crisis.

The fourth recession, which started before Berlusconi stepped down two years ago, is Italy's longest since World War II.

The austerity that Berlusconi helped his successor, Monti, to implement protected Italy from bond market speculation while curbing the investment needed for growth.

Italy's debt more than doubled in nominal terms to 2.07 trillion euros from 1 trillion euros in May 1994, an increase of 32 percent when adjusted for inflation, according to a Bloomberg calculation.

During Berlusconi's tenure as premier, debt per capita rose about 4,030 euros, or 12 percent, at today's prices.