Neb. Rev. Stat. §§ 77-1508
Whenever any county board of equalization shall have reason to believe that any person, company or corporation has not listed all of his or its property for taxation, or that any property has not been fairly valued and assessed, it shall be lawful for such board to call before it any such person, or any agent or officer of any such corporation, and require the production of any books, records or papers. The person so called shall be sworn, and shall answer under oath, and give all information which he may possess, touching the existence, location and value of any property sought to be listed, valued and assessed, and no person so called shall be excused from answering any question put to him on the ground that his answer might tend to criminate him, but no answer he shall make or testimony he may give shall be used against him in any criminal prosecution.
Neb. Rev. Stat. §§ 77-1508