Okla. Stat. tit. 68, § 68-2385.24: State, county and municipal retirement systems -

Withholding.

Beginning July 1, 1989, all state and county retirement systems

whose benefits were exempt from state income taxation prior to

January 1, 1989, and all municipal retirement systems whose benefits

were subject to state income taxation prior to January 1, 1989,

shall begin to withhold monies, as required by Sections 2385.1 et

seq. of this title, for state income tax purposes from the benefits

paid to each member of the retirement systems, unless the member

requests the retirement system not to withhold monies for state

income tax purposes.