18 U.S. Code § 872 – Extortion by officers or employees of the United States
Whoever, being an officer, or employee of the United States or any department or agency thereof, or representing himself to be or assuming to act as such, under color or pretense of office or employment commits or attempts an act of extortion, shall be fined under this title or imprisoned not more than three years, or both; but if the amount so extorted or demanded does not exceed $1,000, he shall be fined under this title or imprisoned not more than one year, or both.
18 U.S. Code § 873 – Blackmail
Whoever, under a threat of informing, or as a consideration for not informing, against any violation of any law of the United States, demands or receives any money or other valuable thing, shall be fined under this title or imprisoned not more than one year, or both.
18 U.S. Code § 880 – Receiving the proceeds of extortion
A person who receives, possesses, conceals, or disposes of any money or other property which was obtained from the commission of any offense under this chapter that is punishable by imprisonment for more than 1 year, knowing the same to have been unlawfully obtained, shall be imprisoned not more than 3 years, fined under this title, or both.