19-3-510. Employment in United States government. (1) A member who is assigned to an agency of the United States government under the Intergovernmental Personnel Act of 1970, 42 U.S.C. 4701, et seq., may purchase the federal employment as service credit in the retirement system under subsection (2) if:

(a) the member has accrued 5 years or more of membership service in the retirement system; and

(b) the member returns to full-time service with the former state or local government employer for at least 1 year after completing employment in the United States government.

(2) A member of the retirement system who is assigned to an agency of the United States government has the option to:

(a) continue the member's payments into the pension trust fund; or

(b) purchase service credit for the period of federal employment under this section within 2 years after return to service under the retirement system.

(3) Salary earned while on assignment to an agency of the United States government must be considered compensation for the purposes of the retirement system and may be included in the determination of highest average compensation if the highest average compensation does not exceed 100% of the member's highest annual compensation earned as a state or local government employee.