"Contempt of Congress is defined in statute, 2 U.S.C.A. § 192, enacted in 1938, which states that any person who is summoned before Congress who "willfully makes default, or who, having appeared, refuses to answer any question pertinent to the question under inquiry" shall be guilty of a misdemeanor and subject to a maximum $1,000 fine and 12 month imprisonment." 
While this statute is phrased as an unconditional obligation, the Fifth Amendment takes precedence over it. For this reason, many witnesses called to testify at Congressional hearings plead the Fifth Amendment and refuse to testify.
Historically, Congress has used three types of contempt citations, civil, criminal, and inherent. In criminal contempt, Congress refers the matter to the Attorney General for criminal prosecution. In civil contempt, Congress files suit in federal court to ask a judge to order compliance with Congressional demands. If a judge orders the subject to comply with congressional demands, and the subject does not comply, that would be a contempt of court — not a contempt of Congress.
Inherent contempt is the power of Congress to hold in contempt and arrest individuals who obstruct performance of the duties of the legislature. The rights of the accused still apply. Under inherent contempt the Legislative branch seizes the arrest powers of the Executive branch and must conduct a trial of the accused which ordinarily is a function of the Judicial branch. Although Congress has a dungeon in its basement where individuals were once held, inherent contempt has not been used since 1935. As of 2019, Congress still does not have rules or statute law to afford due process, counsel, and the right to a speedy trial of the accused.
- In 2012, the full House of Representatives held Attorney General Eric Holder in criminal contempt. Holder subsequently refused to recuse himself for willful violations of law and simply ignored the referral.
- In 2019, Democrat Speaker of the House Nancy Pelosi and Democrat Judiciary Chairman Jerrold Nadler threatened to have a shoot-out between the U.S. Marchall Service, who protect the Attorney General, and the House Sargent-at-Arms who would be charged to enforce an inherent contempt subpoena.