Supervisors in the U.S. Marshals Service Oklahoma office inappropriately retaliated against underlings for cooperating with an inspector general investigation, the watchdog found, a violation of agency rules and the 1978 Inspector General Act.

The three managers, including the chief deputy marshal in the jurisdiction, were found to have exerted undue pressure on subordinates who were cooperating with a prior IG probe, the Justice Department IG reported on Feb. 23. The pressure from supervisors involved demands that the underlings disclose the degree to which they were working with IG investigators, restrictions on work assignments and threats of retaliation.

“The OIG also concluded that the [chief deputy] and the senior inspector lacked candor with the OIG, further violations of department regulations and USMS policy,” the statement read. “The OIG investigation found further that the [marshal] improperly directed a reassigned [deputy] to claim work hours during his daily commute, in violation of federal regulations and USMS travel policy.”

Other allegations against the managers were not substantiated. The conclusions were referred to the deputy attorney general for action, and the retaliation charges to the Office of Special Counsel, though the senior inspector has now retired.

Though the nature of the prior investigation was left unstated, Justice’s IG had been examining the Oklahoma Marshals Service offices for broader allegations such as misuse of government funds, misconduct, wrongful promotional practices and whistleblower retaliation, according to Sen. Chuck Grassley, R-Iowa. As chairman of the Judiciary Committee and a leader of the Senate Whistleblower Protection Caucus, Grassley had referred other cases to the Justice IG.

“This case highlights not only the important roles that inspectors general and whistleblowers play in keeping our government accountable, but also the frequent obstruction and reprisal they face,” Grassley said on Friday. “It is especially disturbing when senior staff at an agency tasked with promoting justice willfully impede internal investigations, punish cooperators, instruct others to break the rules and then misrepresent the facts when they get called out for all of it.”

He called for leadership at the Marshals Service to institute a cultural shift. His comments were echoed by Sen. James Lankford, R-Okla., who said, “Now, Oklahoma leaders and the U.S. Marshals service office must work to ensure that trust and morale is maintained in each office.”