Nebraska Revised Statute 79-9,118
Chapter 79 Section 9,118
Participation in retirement system; qualification.
On and after July 1, 2011, no employee shall be authorized to participate in the retirement system unless the employee (1) is a United States citizen or (2) is a qualified alien under the federal Immigration and Nationality Act, 8 U.S.C. 1101 et seq., as such act existed on January 1, 2009, and is lawfully present in the United States.