Jerri and his son, also named David, contend that Harran and the others fabricated insurance fraud and theft charges against the younger Jerri in 2012 as part of an intimidation campaign that ultimately led the fire chief to resign.
The Jerris said in court filings that the township officials had cited the Fifth Amendment in declining to answer some questions from their lawyer.
Noting such an unusual response, U.S. District Judge Michael Baylson had ordered a hearing next month to review evidence.
Harran, Morgenstern, and the other defendants had declined requests from The Inquirer this week to discuss the claims.
But Friday, the lawyer sent the judge a letter and amended a filing in the case to address the issue. His statement said he amended the defendants' responses to clarify "in plain English that no Fifth Amendment privilege" was being used by DiGirolamo, Harran, Ponticelli, or Monaghan.
In his statement, Morgenstern said he had formally objected to having his clients answer written questions - also known as interrogatories - submitted by the Jerris' lawyer last fall as part of the pretrial routine of sharing evidence during litigation.
One of his objections said that answering the questions "could potentially implicate" his clients' Fifth Amendment rights. But none of the officials actually invoked the right, Morgenstern said Friday.
"I do not intend to assert any such privilege on their behalf," his statement said. "We have nothing to hide."
The younger Jerri was acquitted of theft and insurance fraud in late 2012. With their lawsuit, he and his father are seeking financial damages and reinstatement.
Their lawyer, Brian Wiley, did not return messages Friday for comment.
The personal attorney for DiGirolamo and Harran, Neil A. Morris, said that there had been no depositions in the case yet and that the officials were still seeking to have the case dismissed.