The trial of Sen. Robert Menendez, D-N.J., begins on Wednesday, the first time a U.S. senator faces bribery charges in nearly four decades and a case that could affect the balance of power in the Senate, NBC News reported.
Menendez is accused of doing favors for a Florida eye doctor who allegedly overbilled Medicare, getting "private jet rides and vacations in Paris and the Caribbean" in return, according to prosecutors.
Menendez has said he was simply trying to help an old friend, and the trial will test a recent Supreme Court ruling that narrowed the definition of official bribery. The senator's lawyers say nothing he's accused of qualifies as quid pro quo corruption.
Menendez would likely resist calls to resign if he's convicted, and while he could be expelled, that would take a two-thirds vote, something that hasn't been done in 155 years. His successor would be appointed by the governor of New Jersey, currently Republican Chris Christie.