Sexual Abuse
By force or threat.--Whoever, in the special maritime and territorial jurisdiction of the United States or in a Federal prison, or in any prison, institution, or facility in which persons are held in custody by direction of or pursuant to a contract or agreement with the Attorney General, knowingly causes another person to engage in a sexual act
(1) by using force against that other person; or
(2) by threatening or placing that other person in fear that any person will be subjected to death, serious bodily injury, or kidnapping; or attempts to do so, shall be fined under this title, imprisoned for any term of years or life, or both.