Nebraska Revised Statute 18-809
Chapter 18
18-809.
Board; member; oath; bond.
Each member of the board, before entering upon the duties of office, shall file with the city clerk or village clerk of the municipality in which he or she resides an oath that he or she will duly and faithfully perform all the duties of the office to the best of his or her ability and a bond in the penal sum of five thousand dollars executed by one or more qualified sureties for the faithful performance of his or her duties. If any member fails to file such oath and bond on or before the first day of the term for which he or she was appointed or elected, his or her office shall be deemed to be vacant.