14 U.S.C. § 304

1. (a)
   1. (1)A Commandant who is not reappointed shall be retired with the grade of admiral at the expiration of the appointed term, except as provided in section 306(d) of this title.
   2. (2)A Vice Commandant who is retired while serving as Vice Commandant, after serving not less than 2 years as Vice Commandant, shall be retired with the grade of admiral, except as provided in section 306(d).
2. (b)A Commandant or Vice Commandant who is retired for physical disability shall be placed on the retired list with the grade of admiral.
3. (c)An officer who is retired prior to the expiration of the officer’s term, while serving as Commandant or as an officer serving as Vice Commandant who has served less than 2 years as Vice Commandant, may, in the discretion of the President, be retired with the grade of admiral.
4. (d)Retirement under this section is subject to section 2501(a) of this title.