Obstruction of Justice: 18 USC 1505

"....Whoever corruptly,

or by threats or force,
or by any threatening letter
or communication

influences,
obstructs,
or impedes
or endeavors to influence, obstruct, or impede

the due and proper
administration of the law
under which any pending proceeding
is being had before any department
or agency of the United States,

or

the due and proper
exercise of the power of inquiry
under which any inquiry or investigation
is being had
by either House,
or any committee of either House
or any joint committee of the Congress—


Shall

be fined under this title,
imprisoned not more than 5 years

or,

if the offense involves international or domestic terrorism
(as defined in section 2331),
imprisoned not more than 8 years,

or both."

(Author: U.S. Congress)

More information
http://rewinn.com/18usc1505