This is a brief description of those that outlaw interference with congressional activities. 1512 (tampering with federal witnesses), 1513 (retaliating against federal witnesses), 1503 (obstruction of pending federal court proceedings), 1505 (obstruction of pending congressional or federal administrative proceedings), 371 (conspiracy), and contempt. All but §1503 apply to congressional activities. Witness Tampering (18 U.S.C. "The elements of misprision of a felony under 18 U.S.C. corruptly
III. Prosecutions under §1505 have been relatively few, at least until recently, and most of these arise as obstructions of administrative proceedings. Obstruction of Justice by Violence or Threat

In addition to the basic federal crimes of obstruction of justice, federal law features a host of criminal statutes that proscribe various obstructions according to the obstructive means used, be it physical violence, bribery, property destruction, or deception. In the wake of McNally , Congress expanded the scope of the mail and wire fraud statutes with the passage of 18 U.S.C. Mail fraud and wire fraud are both RICO and money laundering predicate offenses. 371 is an alternative. Obstruction of Justice by Destruction of Evidence

Other than subsection 1512(c), three federal statutes expressly outlaw the destruction of evidence in order to obstruct justice, only one of which may apply to obstruction of Congress: 18 U.S.C. The laws relating to aiding and abetting, accessories after the fact, misprision, and conspiracy, however, apply to all four. §3C1.1)

Regardless of the offense for which an individual is convicted, his sentence may be enhanced as a consequence of any obstruction of justice for which he is responsible, if committed during the course of the investigation, prosecution, or sentencing for the offense of his conviction. The enhancement may result in an increase in his term of imprisonment by as much as 4 years. The examples in the section's commentary cover conduct: 
(B) committing, suborning, or attempting to suborn perjury, including during the course of a civil proceeding if such perjury pertains to conduct that forms the basis of the offense of conviction;
(F) providing materially false information to a judge or magistrate;
(G) providing a materially false statement to a law enforcement officer that significantly obstructed or impeded the official investigation or prosecution of the instant offense;
(H) providing materially false information to a probation officer in respect to a presentence or other investigation for the court; [and]
(I) other conduct prohibited by obstruction of justice provisions under Title 18, United States Code (e.g., 18 U.S.C.
Obstruction of justice is the impediment of governmental activities. There are a host of federal criminal laws that prohibit obstructions of justice. The six most general outlaw obstruction of judicial proceedings (18 U.S.C. 1503), witness tampering (18 U.S.C. 1512), witness retaliation (18 U.S.C. 1513), obstruction of congressional or administrative proceedings (18 U.S.C. 1505), conspiracy to defraud the United States (18 U.S.C. 371), and contempt (a creature of statute, rule and common law). All but Section 1503 cover congressional activities.
The laws that supplement, and sometimes mirror, the basic six tend to proscribe a particular means of obstruction. Some, like the perjury and false statement statutes, condemn obstruction by lies and deception. Others, like the bribery, mail fraud, and wire fraud statutes, prohibit obstruction by corruption. Some outlaw the use of violence as a means of obstruction. Still others ban the destruction of evidence. A few simply punish "tipping off" those who are the targets of an investigation. A good number of these apply in a congressional context.
Many of these offenses may also provide the basis for racketeering and money laundering prosecutions, and each provides the basis for criminal prosecution of anyone who aids and abets in or conspires for their commission.
Moreover, regardless of the offense for which an individual is convicted, his sentence may be enhanced as a consequence of any obstruction of justice for which he is responsible, if committed during the course of the investigation, prosecution, or sentencing for the offense of his conviction. The enhancement may result in an increase in his term of imprisonment by as much as four years.
This report is available in abbreviated form—without footnotes, quotations, or citations—as CRS Report RS22784, Obstruction of Congress: An Abridged Overview of Federal Criminal Laws Relating to Interference with Congressional Activities. Both versions have been excerpted from CRS Report RL34303, Obstruction of Justice: an Overview of Some of the Federal Statutes that Prohibit Interference with Judicial, Executive, or Legislative Activities. Other excerpted portions are also available as the following: CRS Report RS22783, Obstruction of Justice: An Abridged Overview of Related Federal Criminal Laws; CRS Report 98-808, Perjury Under Federal Law: A Brief Overview; and CRS Report 98-807, Perjury Under Federal Law: A Sketch of the Elements, all by [author name scrubbed].