(a) Whoever commits an offense against the United States or aids, abets, counsels, commands, induces or procures its commission, is punishable as a principal.
(b) Whoever willfully causes an act to be done which if directly performed by him or another would be an offense against the United States, is punishable as a principal.
Whoever, knowing that an offense against the United States has been committed, receives, relieves, comforts or assists the offender in order to hinder or prevent his apprehension, trial or punishment, is an accessory after the fact.
Except as otherwise expressly provided by any Act of Congress, an accessory after the fact shall be imprisoned not more than one-half the maximum term of imprisonment or (notwithstanding section 3571) fined not more than one-half the maximum fine prescribed for the punishment of the principal, or both; or if the principal is punishable by life imprisonment or death, the accessory shall be imprisoned not more than 15 years.
Whoever, having knowledge of the actual commission of a felony cognizable by a court of the United States, conceals and does not as soon as possible make known the same to some judge or other person in civil or military authority under the United States, shall be fined under this title or imprisoned not more than three years, or both.