((a))
((1)) For the purpose of determining the grade and rank within grade of a person receiving an original appointment in a commissioned grade (other than a warrant officer grade) in the Regular Army, Regular Navy, Regular Air Force, Regular Marine Corps, or Space Force, such person shall be credited at the time of such appointment with any active commissioned service (other than service as a commissioned warrant officer) that he performed in any armed force, the National Oceanic and Atmospheric Administration, or the Public Health Service before such appointment.
((2)) The Secretary of Defense shall prescribe regulations, which shall apply uniformly among the Army, Navy, Air Force, Marine Corps, and Space Force, to authorize the Secretary of the military department concerned to limit the amount of prior active commissioned service with which a person receiving an original appointment may be credited under paragraph (1), or to deny any such credit, in the case of a person who at the time of such appointment is credited with constructive service under subsection (b).
((b))
((1)) Under regulations prescribed by the Secretary of Defense, the Secretary of the military department concerned shall credit a person who is receiving an original appointment in a commissioned grade (other than a commissioned warrant officer grade) in the Regular Army, Regular Navy, Regular Air Force, Regular Marine Corps, or Space Force and who has advanced education or training or special experience with constructive service for such education, training, or experience as follows:
((A)) One year for each year of advanced education beyond the baccalaureate degree level, for persons appointed, designated, or assigned in officer categories requiring such advanced education or an advanced degree as a prerequisite for such appointment, designation, or assignment. In determining the number of years of constructive service to be credited under this clause to officers in any professional field, the Secretary concerned shall credit an officer with, but with not more than, the number of years of advanced education required by a majority of institutions that award degrees in that professional field for completion of the advanced education or award of the advanced degree.
((B))
((i)) Credit for any period of advanced education in a health profession (other than medicine and dentistry) beyond the baccalaureate degree level which exceeds the basic education criteria for appointment, designation, or assignment, if such advanced education will be directly used by the armed force concerned.
((ii)) Credit for experience in a health profession (other than medicine or dentistry), if such experience will be directly used by the armed force concerned.
((C)) Additional credit of (i) not more than one year for internship or equivalent graduate medical, dental, or other formal professional training required by the armed forces, and (ii) not more than one year for each additional year of such graduate-level training or experience creditable toward certification in a specialty required by the armed forces.
((D)) Additional credit as follows:
((i)) For special training or experience in a particular officer field as designated by the Secretary concerned, if such training or experience is directly related to the operational needs of the armed force concerned.
((ii)) During fiscal years 2021 through 2025, for advanced education in an officer field so designated, if such education is directly related to the operational needs of the armed force concerned.
((E)) Additional credit for experience as a physician or dentist, if appointed as a medical or dental officer in the Army or Navy or, in the case of the Air Force, with a view to designation as a medical or dental officer.
((2)) The amount of constructive service credited an officer under this subsection may not exceed the amount required in order for the officer to be eligible for an original appointment in the grade of colonel in the Army, Air Force, Marine Corps, or Space Force, or captain in the Navy.
((3)) Constructive service credited an officer under this subsection is in addition to any service credited that officer under subsection (a) and shall be credited at the time of the original appointment of the officer.
((c)) Constructive service credited an officer under subsection (b) shall be used only for determining the officer’s—
((1)) initial grade as a regular officer;
((2)) rank in grade; and
((3)) service in grade for promotion eligibility.
((d))
((1)) Constructive service may not be credited under subsection (b) for education, training, or experience obtained while serving as a commissioned officer (other than a warrant officer) on active duty or in an active status. However, in the case of an officer who completes advanced education or receives an advanced degree while on active duty or in an active status and in less than the number of years normally required to complete such advanced education or receive such advanced degree, constructive service may, subject to regulations prescribed under subsection (a)(2), be credited to the officer under subsection (b)(1)(A) to the extent that the number of years normally required to complete such advanced education or receive such advanced degree exceeds the actual number of years in which such advanced education or degree is obtained by the officer.
((2)) A graduate of the United States Military Academy, the United States Naval Academy, or the United States Air Force Academy is not entitled to service credit under this section for service performed, or education, training, or experience obtained, before graduation from such Academy.
((e)) If the Secretary of Defense determines that the number of qualified judge advocates serving on active duty in the Army, Navy, Air Force, or Marine Corps in grades below major or lieutenant commander is critically below the number needed by such armed force in such grades, he may authorize the Secretary of the military department concerned to credit any person receiving an original appointment in the Judge Advocate General’s Corps of the Army or Navy, or any person receiving an original appointment in the Air Force or Marine Corps with a view to designation as a judge advocate, with a period of constructive service in such an amount (in addition to any period of service credited such person under subsection (b)(1)) as will result in the grade of such person being that of captain or, in the case of an officer of the Navy, lieutenant and the date of rank of such person being junior to that of all other officers of the same grade serving on active duty.
((f)) A reserve officer (other than a warrant officer) who receives an original appointment as an officer (other than as a warrant officer) in the Regular Army, Regular Navy, Regular Air Force, Regular Marine Corps, or Space Force shall—
((1)) in the case of an officer on the active-duty list immediately before that appointment as a regular officer, be appointed in the same grade and with the same date of rank as the grade and date of rank held by the officer on the active-duty list immediately before the appointment; and
((2)) in the case of an officer not on the active-duty list immediately before that appointment as a regular officer, be appointed in the same grade and with the same date of rank as the grade and date of rank which the officer would have held had the officer been serving on the active-duty list on the date of the appointment as a regular officer.