It is unlawful for any person, without justifiable or excusable cause, to knowingly commit any assault, battery or assault and battery upon the person of a police officer, sheriff, deputy sheriff, highway patrolman, corrections personnel, or state peace officer employed or duly appointed by any state governmental agency to enforce state laws while in the performance of his or her duties.
(21 O.S. § 649) (`83 Code, § 10-603) Penalty, see § 10.99