46 U.S.C. § 7511

1. (a)A license, certificate of registry, or merchant mariner’s document authorized to be issued under this part shall be denied to an individual who has been convicted of a sexual offense prohibited under—
   1. (1)chapter 109A of title 18, except for subsection (b) of section 2244 of title 18;
   2. (2)section 920 or 920b of title 10 (article 120 and 120b of the Uniform Code of Military Justice); or
   3. (3)a substantially similar offense under Federal, State, local, or Tribal law.
2. (b)A license, certificate of registry, or merchant mariner’s document authorized to be issued under this part may be denied to an individual who within 5 years before applying for the license, certificate, or document, has been convicted of a sexual offense prohibited under subsection (b) of section 2244 of title 18, or a substantially similar offense under State, local, or Tribal law.