One evening in 1996, as the Yankees clinched their first World Series in 18 years, Donald J. Trump was presiding over a masquerade ball at his sprawling Westchester County estate.

Mr. Trump intended to convert the home, a limestone mansion called Seven Springs, into a golf club, and he had recruited one of the county’s best-connected lawyers to help him do it: Albert J. Pirro Jr. The costume party was a lavish fund-raiser for Mr. Pirro’s wife, the Westchester district attorney, who greeted dozens of masked guests in her own striking get-up.

Jeanine F. Pirro had dressed as Queen Isabella of Spain.

“I was at the ballgame with George Steinbrenner, and it was great, just great,” Mr. Trump told an attendee at the time. “But this is just great, too.”

At the time, Ms. Pirro seemed destined for political stardom. Her fiery style had earned her a spot on the national TV circuit as a pundit on the O. J. Simpson case. The New Yorker was preparing a fawning profile, complete with Helmut Newton portrait. A run for lieutenant governor was in the offing; a United States Senate seat not out of the question.