Testimony begins in trial of Sen. Bob Menendez

NEW JERSEY (FOX 5 NEWS) - Federal prosecutors had a rough start on the first day of testimony in the bribery trial of Sen. Bob Menendez, Democrat of New Jersey.

Prosecutors called FBI analyst Jane Ruch to testify about a $1,500-per-night ritzy Paris hotel stay that the senator didn't pay for. However, Judge William Walls interrupted her testimony to remind both prosecutors and the defense that their questions should be more "direct and specific." (Dr. Melgen paid for that Paris hotel stay in April 2010.)

Menendez is accused of accepting unlawful gifts and donations from Florida eye surgeon Dr. Salomon Melgen.

A conviction would require the Democrat to give up his seat -- the timing of which seriously impacts Capitol Hill. If he has to step down while Gov. Chris Christie is in office would surely guarantee a Republican appointee.

Menendez left court Thursday in good spirits. He maintains his innocence and expects to be vindicated by the jury.

And if Republicans are watching this trial, Democrats are also. Sen. Cory Booker, Menendez's colleague from New Jersey, was at the trial.

Testimony resumes in federal court on Monday.