Okla. Stat. tit. 19, § 516

A. It shall be the duty of the sheriff, undersheriffs and deputies to keep and preserve the peace of their respective counties, and to quiet and suppress all affrays, riots and unlawful assemblies and insurrections, for which purpose and for the service of process in civil and criminal cases, and in apprehending or securing any person for felony or breach of the peace, they and every constable may call to their aid such person or persons of their county as they may deem necessary. B. The sheriff, in addition to the duties pursuant to subsection A of this section, shall coordinate and administer courthouse security.