It shall be the duty of the sheriff by himself or deputy to preserve the peace in his county, to ferret out crime, to apprehend and arrest all criminals, and insofar as it is within his power, to secure evidence of all crimes committed in his county, and present the same to the county attorney and the grand jury; to file informations against all persons who he knows, or has reason to believe, have violated the laws of the state, and to perform all other duties pertaining to the office of sheriff.
Neb. Rev. Stat. §§ 23-1710