Congress's Contempt Power and the Enforcement of Congressional Subpoenas: Law, History, Practice, and Procedure [May 8, 2014] [open pdf - 826KB]
"Congress's contempt power is the means by which Congress responds to certain acts that in its view obstruct the legislative process. Contempt may be used either to coerce compliance, to punish the contemnor, and/or to remove the obstruction. Although arguably any action that directly obstructs the effort of Congress to exercise its constitutional powers may constitute a contempt, in recent times the contempt power has most often been employed in response to noncompliance with a duly issued congressional subpoena--whether in the form of a refusal to appear before a committee for purposes of providing testimony, or a refusal to produce requested documents. […] This report examines the source of the contempt power, reviews the historical development of the early case law, outlines the statutory and common law basis for Congress's contempt power, and analyzes the procedures associated with inherent contempt, criminal contempt, and the civil enforcement of subpoenas. The report also includes a detailed discussion of two recent information access disputes that led to the approval of contempt citations in the House against then-White House Chief of Staff Joshua Bolten and former White House Counsel Harriet Miers, as well as Attorney General Eric Holder. Finally, the report discusses both non-constitutional and constitutionally based limitations on the contempt power."
CRS Report for Congress, RL34097