Lois Lerner, the IRS official who refused to testify at a House hearing, faces criticism over the agency's practice of singling out conservative groups and her Federal Elections Commission history.

Lawmakers Voice Frustration as IRS Official Refuses to Testify, Others Reveal Little

VIDEO: Lerner: 'I Did Nothing Wrong'

OPINION: Chicago-Style Politics on Full Display in IRS, Other Scandals

FOX NEWS POLL: Most Voters Want Guantanamo Kept Open

Obama Administration Says Drone Strikes Have Killed 4 Americans

VIDEO: Drones Kill 4 Americans

READ: Attorney General Holder's Letter to Congressional Leaders