The trouble with Silvio Berlusconi is that he is unique only in the extent of his wealth and the brazenness with which he flouts the law. That's why, even after the Italian Senate stripped him of his seat last night, his story won't be over until Prime Minister Enrico Letta and his government enact electoral reform to clean out the stables in Rome.

Berlusconi is finished as a political leader, but he remains a force with the power to destroy and disrupt. Italians who oppose him often despair at what his continued popularity says about their nation as a whole -- but in truth, Italians are consistent. Pro- and anti-Berlusconi Italians alike are depressed by the whole political class. That's why a quarter of voters in February's elections backed the upstart Five Star Movement, led by an essentially anarchist former comedian.

Why, then, pick on Berlusconi if other mainstream politicians are the same, just less entertaining?

The country's 951 legislators are grossly overpaid and enjoy an absurd range of privileges that they have carved out for themselves over the years. After Mario Monti took over as prime minister in 2011, he commissioned a report that showed Italian MPs were earning more than 16,000 euros ($22,000) per month, including expenses -- more than double their French and British counterparts.

Too often, they are also corrupt. Berlusconi is facing trial for allegedly bribing a left-wing senator to switch to his party in order to bring down the government in 2006. Who was shocked at the charge? The country got its first real anti-corruption law just a year ago; a Council of Europe report in 2009 dismissed the parliament's code of conduct as "aspirational"; and, according to a Transparency International survey this year, 89 percent of Italians believe their political parties are corrupt. Like Berlusconi, Italy's legislators have not done their job, which is to legislate for the improvement of the Italian economy and nation.

That's why, as much as Italy desperately needs rapid economic reform to lead it out of its secular economic decline, the most urgent task facing Letta and his coalition government is electoral reform. Italy needs a new electoral law that, as a panel of so-called wise men recommended to President Giorgio Napolitano earlier this year, would dramatically reduce the number of legislators at the public trough in Rome; redistribute powers from the Senate to the House; and change the voting system to make it more majoritarian, ensuring that a winner emerges who can govern. While they're at it, they should scrap all the chauffeur-driven cars and other privileges of office, redrawing them from scratch.

Berlusconi's instinct for dramatic schlock is second to none, as his performance during the Senate vote yesterday showed. Rather than be present for his defeat, he told a crowd of supporters that this was a "day of mourning for democracy." So, the bunga-bunga prime minister, who personalized the Italian state by driving through laws tailored to protect his own liberty and interests from due process, presents himself as the touchstone for Italian democracy.

With a more or less professional and functional government in office, Italians would see Berlusconi for the millstone, and exception, that he is.

(Marc Champion is a Bloomberg View editorial board member. Follow him on Twitter.)