A congressional panel on Tuesday called on the Commerce Department’s top watchdog to fire his top two managers in charge of whistleblower protections after investigators determined they tried to silence two former employees.

The demands stem from an Office of Special Counsel probe that found the senior officials had threatened subordinates with negative performance reviews if they did not sign gag agreements before moving to new jobs.

All of the members of a House subcommittee that oversees the Commerce Department signed a letter calling on the agency’s inspector general, Todd Zinser, to fire the managers immediately. They described the actions as “a thinly veiled effort to intimidate whistleblowers into not reporting misconduct.”

“I would interpret inaction by the IG on this matter to mean support for the two [officials’] actions, in which case we have a bigger problem in that office,” said Rep. Paul Broun (R-Ga.), who heads the subcommittee.

The Office of Special Counsel examined Zinser’s role in the alleged misconduct and found no direct “documentary evidence” that he was aware of it, according to the letter.

Zinser, who was appointed to his position by President George W. Bush, signaled reluctance to fire the officials on Tuesday, saying in a statement that his office had already implemented a number of changes in response to the Special Counsel’s findings.

The corrective actions included removing the managers from supervisory duties for one year, establishing consistent guidelines for employee-separation agreements and destroying all copies of the negative performance reviews.

“We worked cooperatively with OSC throughout their investigation and took their concerns seriously,” Zinser said. “We have moved on and continue to focus on providing oversight of the programs and operations of the Department of Commerce.”

The inspector general also noted that the Office of Special Counsel had closed its case because of the actions that his office had agreed to.

The lawmakers described Zinser’s response to the investigation and its findings as “entirely insufficient and contemptuous.” They said his failure to already fire the senior officials suggests “complicity with the actions of your senior-most staff.”

Zinser accused two of his agents in December 2012 of waging a smear campaign against his office while they were under investigation for filing false expense claims and clocking hours they didn’t work.

The former employees, Rachel Ondrik and Kirk Yamatani, pleaded guilty in May to charges of time and attendance fraud. They agreed to probation and $42,000 each in fines and restitution to the U.S. government.

A U.S. District Court judge allowed the two agents to withdraw their pleas upon appeal after determining that the magistrate judge who handled their cases had not followed proper procedures. The matter is now pending with prosecutors again, according to Steven Levin, an attorney for Yamatani.

Prior to their plea agreements, the two agents filed complaints against Zinser’s office with the FBI, the U.S. Attorney’s Office, and the secretary of commerce, according to records obtained by The Washington Post. However, the Office of Special Counsel said in May that the employees were not involved in the whistleblower case against the inspector general’s office.

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