According to lawyers involved in the case , Monmouth County investigators asked an assortment of questions about a contractor who , at the time , was working as a confidential informant for the F.B.I . But Mr. Kaye insisted that his office was working on its own corruption case and interviewed the two public officials -- Keyport 's mayor , John J. Merla , and a former borough councilman , Robert L. Hyer -- only after clearing the matter with the United States attorney , Christopher J. Christie , in a telephone conversation .