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). 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. Many of these offences 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.