(1) Every member of the Nebraska State Patrol who was employed by the State of Nebraska as such, on September 7, 1947, and every person employed as a member of such patrol thereafter, shall be a member of the system, except for those members of the Nebraska State Patrol who elected pursuant to section 60-1304 to remain members of the State Employees Retirement System of the State of Nebraska.

(2) No employee shall be authorized to participate in the retirement system provided for in the Nebraska State Patrol Retirement Act unless the employee is a United States citizen or is lawfully present in the United States. The employing state agency and the employee shall maintain at least one of the following documents which shall be unexpired, if applicable to the particular document, to demonstrate United States citizenship or lawful presence in the United States as of the employee's date of hire and produce any such document so maintained upon request of the board or the Nebraska Public Employees Retirement Systems:

(a) A state-issued driver's license;

(b) A state-issued identification card;

(c) A certified copy of a birth certificate or delayed birth certificate issued in any state, territory, or possession of the United States;

(d) A Consular Report of Birth Abroad issued by the United States Department of State;

(e) A United States passport;

(f) A foreign passport with a United States visa;

(g) A United States Certificate of Naturalization;

(h) A United States Certificate of Citizenship;

(i) A tribal certificate of Native American blood or similar document;

(j) A United States Citizenship and Immigration Services Employment Authorization Document, Form I-766;

(k) A United States Citizenship and Immigration Services Permanent Resident Card, Form I-551; or

(l) Any other document issued by the United States Department of Homeland Security or the United States Citizenship and Immigration Services granting employment authorization in the United States and approved by the board.

(3) Within the first one hundred eighty days of employment, a member may apply to the board for eligibility and vesting credit for years of participation in another Nebraska governmental plan, as defined by section 414(d) of the Internal Revenue Code. During the years of participation in the other Nebraska governmental plan, the employee must have been a full-time employee, as defined in the Nebraska governmental plan in which the credit was earned.

(4) Any officer who qualifies for membership pursuant to subsection (1) of this section may not be disqualified from membership in the retirement system solely because such officer also maintains separate employment which qualifies the officer for membership in another public retirement system, nor may membership in this retirement system disqualify such an officer from membership in another public retirement system solely by reason of separate employment which qualifies such officer for membership in this retirement system.

(5) Information necessary to determine membership shall be provided by the Nebraska State Patrol.

(6) The board may adopt and promulgate rules and regulations governing the assessment and granting of eligibility and vesting credit.