When Assemb. Eric Stevenson was swiftly convicted of bribery and fraud this week, the Bronx Democrat's guilty verdicts became the most recent link in a chain of corruption that has shackled the borough for years.

A jury found that Stevenson, who represented poverty-afflicted Morrisania and East Tremont, took $22,000 in bribes to deliver a monopoly of adult-care centers to Russian businessmen. The bribe-receiving was so brazen that the day after he pocketed a $10,000 payoff, he sped to a dealership to put down $500 on a Jaguar. He's called the case unfair.

Not only did he sell out his constituents' trust and his family name -- both his father and grandfather were in politics -- Stevenson joined a pantheon of politicians whose greed and self-indulgence have fed a pernicious narrative about the Bronx. In 2010, the powerful Democratic state Sen. Efrain Gonzalez Jr. was sentenced to seven years in prison after he stole $700,000 from nonprofits. Two years later, a jury found that the bellicose Pedro Espada Jr., by then a former Democratic state senator, stole nearly $448,000 from the Soundview Health Center he founded. And in November, former Bronx County Republican chairman Joseph Savino admitted to pocketing $15,000 to sell a Democratic state senator the Republican line in last year's mayoral race.

Independently, the convictions amount to career-ending avarice and cynicism. Collectively, they bespeak the charade that is one-party rule -- Democrats control the Bronx -- and underscore the collateral damage from unrestrained hubris.

During an era when NYC has undergone a renaissance -- bringing renewed interest, vitality and wealth to Brooklyn and Queens -- the Bronx struggles with the city's highest level of poverty, the state's lowest level of employment and some of the nation's starkest health statistics.

The borough has had some recent gains -- including the coming Metro Center Atrium on the Hutchinson River Parkway and the redevelopment of the historic Kingsbridge Armory.

They should be seeds of something more substantial. But first, the Bronx needs more politicians with vision that extends beyond themselves.

Eli Reyes is deputy editorial page editor for amNewYork.