“I urge you to remove her,” Wyden wrote.

Wyden’s letter comes as Ennis, a 2019 Trump administration appointee, faces multiple long-running investigations into her leadership, including oversight of a $200 billion disability benefits program administered by Social Security. Ennis has drawn particular scrutiny for an anti-fraud program run by the inspector general’s office that leveled large penalties against disabled claimants — and for allegedly retaliating against staffers who raised alarms about that practice, which began under Ennis’s predecessor and continued on her watch.

Wyden’s letter also cited issues raised by the Federal Law Enforcement Officers Association, which in 2021 voted “no confidence” in her because of “erroneous policies that hamper investigative capacity.”

Furthermore, “staff morale has worsened,” Wyden wrote, noting that her office ranked second to last out of 432 agencies in the Partnership for Public Service’s Best Places to Work in the Federal Government 2022 rankings, the latest available. That’s an improvement over 2021, when Ennis’s office was last in its category for employee engagement.

Rebecca Rose, a spokeswoman for Ennis, defended the inspector general’s conduct and told The Washington Post that Ennis “has been consistently and thoroughly responsive to Chairman Wyden, meeting with his staff and sending multiple letters regarding his concerns.”

The White House did not immediately respond to a message about the letter.

In May 2022, The Post reported on the scope of the anti-fraud program’s fines, including unprecedented penalties against more than 100 beneficiaries without due process. The fines went against previous procedures, which called for the agency to take into account financial status, remorse and other factors. Instead, mostly poor and disabled people were ordered to pay fines as high as hundreds of thousands of dollars.

Following the story, Democratic leaders of the House Ways and Means Committee said “we are outraged by this stunning report,” and acting SSA commissioner Kilolo Kijakazi began probing the inspector general’s oversight of the disability benefits program.

The Office of Special Counsel, an independent agency that protects federal whistleblowers, and the Council of the Inspectors General on Integrity and Efficiency (CIGIE), a government-wide watchdog agency that oversees inspector general issues, also opened inquiries into Ennis’s operation.

The probes by Kijakazi, the CIGIE and the Office of Special Counsel remain open.

In July, Wyden demanded answers from Ennis in an 11-page letter citing the recurrent allegations of low productivity and retaliation. Wyden also complained in a November letter about a defamation lawsuit filed by the inspector general’s chief counsel against two whistleblowers. (That lawsuit also names The Post and other defendants.)

“I urge you to take immediate action to bring new leadership to SSA OIG,” Wyden told Biden in the new letter, “so the office can focus on its vital work overseeing the administration of Social Security programs and operations.”