The absence of testimony from Lois Lerner will shift focus to Deputy Treasury Secretary Neal Wolin at today’s House Committee on Oversight and Government hearing on the IRS scandal.

A lawyer for Lerner, the head of the IRS tax-exempt section who first revealed the agency had targeted conservative groups for closer scrutiny, told lawmakers on Tuesday that Lerner intends to invoke her Fifth Amendment right. In statements made prior to the hearing, Lerner said that low-level employees at the IRS’ Cincinnati office had flagged groups applying for tax-exempt status if they had the words “tea party” or “patriot” in their name. She has been subpoenaed by committee Chairman Darrell Issa to appear before the committee.

In the meantime, Wolin has called the IRS’ mistreatment of specific groups “absolutely unacceptable and inexcusable.”

“The IRS must operate without bias or even the perception of bias,” he wrote in a written testimony to lawmakers. “It must act in an utterly nonpartisan manner. It must act with the utmost integrity. The IRS did not do that here.”

He reiterated to lawmakers what many IRS officials and an inspector general report already found: that there is no indication his department was involved in the scandal.