IRS' Lerner was asked to resign, refused: GOP Sen.

Insisting that she's "done nothing wrong," Lois Lerner, the IRS official in charge of the division that targeted conservative nonprofit groups for additional scrutiny of their applications for tax-exempt status, invoked her Fifth Amendment right against self-incrimination during a congressional testimony.

Before she was placed on administrative leave, Lois Lerner, the head of the tax-exempt organizations division of the IRS, was asked to resign but refused, according to a Republican senator.

"My understanding is the new acting IRS commissioner asked for Ms. Lerner's resignation, and she refused to resign," Sen. Chuck Grassley, R-Iowa, said in a statement. "She was then put on administrative leave instead. From all accounts so far, the IRS acting commissioner was on solid ground to ask for her resignation."

Lerner oversaw the division of the IRS responsible for putting undue scrutiny on conservative groups applying for tax-exempt status and has come under fire for failing to notify Congress of the misconduct.

Grassley, a top Republican on the Senate Finance Committee, said in his statement, "The IRS owes it to taxpayers to resolve her situation quickly. The agency needs to move on to fix the conditions that led to the targeting debacle. She shouldn't be in limbo indefinitely on the taxpayers' dime."

Because she's on administrative leave, Lerner gets to keep her full salary.

The new acting IRS commissioner Danny Werfel, who took over the agency on Wednesday, named 27-year IRS veteran Ken Corbin as Lerner's replacement.