As Menendez’s Star Rose, Fears of Corruption Cast a Persistent Shadow

Robert Menendez’s education in political corruption came unusually early. In 1982, he turned against his mentor, Mayor William V. Musto of Union City, N.J., the popular leader of their gritty hometown.

Mr. Menendez took the witness stand and testified that city officials had pocketed kickbacks on construction projects, helping to put a man widely seen as his father figure behind bars. Mr. Menendez, then 28, wore a bulletproof vest for a month.

The episode, which Mr. Menendez has used to cast himself as a gutsy Democratic reformer, helped fuel his remarkable rise from a Jersey tenement to the pinnacles of power in Washington as the state’s senior senator. The son of Cuban immigrants, Mr. Menendez broke barriers for Latinos and has used his perch as chairman of the Senate Foreign Relations Committee to influence presidents and prime ministers.

But those who have closely followed his career say the years he spent enmeshed in Mr. Musto’s machine also set the tone for another, more sinister undercurrent that now threatens to swallow it — one in which Mr. Menendez became a power broker himself whose own close ties to moneyed interests have repeatedly attracted the scrutiny of federal prosecutors.

Those two sides of his life collided on Wednesday in federal court in Manhattan, where Mr. Menendez, 69, surrendered to face his second bribery indictment in less than a decade.