Unprompted, Hatch said he has a good relationship with Koskinen. It's an influential statement of support because Hatch serves as Senate president pro tem — making him third in line to succeed the president. Hatch also led the Senate Finance Committee investigation of allegations the IRS targeted conservative groups for audits, and said Koskinen cooperated.
But Hatch's backing may not be enough to counter the ire against Koskinen from other Republicans, some of whom want him to step down before his five-year-term ends in November.
On Wednesday, 15 GOP members of the House Ways and Means Committee said trust in the IRS has hit rock bottom. They said that under Koskinen, the IRS destroyed evidence when Congress was investigating the tax agency for inappropriately singling out conservative groups for extra scrutiny.
"He also misled Congress in the process, intentionally degraded customer service at the agency, and has since lost the trust of the American people," the committee members wrote.
Rep. Kevin Brady, R-Texas, chairman of the Ways and Means Committee, pointedly said he would not be inviting Koskinen to testify about the tax filing season.
Despite the fact that Koskinen was not at the IRS during the scandal over conservative groups, he has become a favorite whipping boy of House Republicans. They complained that he was slow to comply with their requests for information, hauling him before congressional panels dozens of times — sometimes just to berate him.
President Barack Obama appointed Koskinen to the aftermath of the scandal over conservative groups. Koskinen is a turnaround specialist with extensive experience in the public and private sectors.
He came in to overhaul mortgage buyer Freddie Mac after its near-collapse in the financial crisis at the end of President George W. Bush's administration. He also helped restructure the assets of the largest failed life insurance company in U.S. history, Mutual Benefit Life, and helped reorganize the Penn Central Transportation Co. after it became the largest bankruptcy in U.S. history.
Koskinen said he has not heard from anyone in the Trump administration about stepping down.
But in tense exchange at Thursday's hearing, Sen. Pat Roberts, R-Kan., asked Koskinen if he intends to finish his term.
"It gives me no pleasure and some degree of sadness," Roberts said. "I have been disappointed in your record at the agency."
Koskinen replied, "I regret that you're disappointed in the performance."
Koskinen went on to defend his record. He said the IRS has implemented every recommendation from every investigation into the IRS handling of conservative groups. He said no one at the tax agency hindered any of the investigations.
— Tribune staff contributed to this report