Okla. Stat. tit. 11 § 34-106
The State of Oklahoma hereby declares and states that the increased number of persons impersonating law enforcement officers by making routine traffic stops while using unmarked cars is a threat to the public health and safety of all the citizens of the State of Oklahoma; therefore it shall be unlawful for any municipal police department to use any vehicle which is not clearly marked as a law enforcement vehicle for routine traffic enforcement except as provided in Section 12-218 of Title 47 of the Oklahoma Statutes. In addition to Section 12-218 of Title 47 of the Oklahoma Statutes, the peace officer operating the law enforcement vehicle for routine traffic stops shall be dressed in the official uniform including shoulder patches, badge, and any other identifying insignias normally used by the employing law enforcement agency.
Okla. Stat. tit. 11, § 34-106