(a) The commissioners court of a county may establish under this chapter a drug court program exclusively for persons arrested for, charged with, or convicted of an offense involving the operation of a motor vehicle while intoxicated.
(b) A county that establishes a drug court program under this chapter but does not establish a separate program under this section must employ procedures designed to ensure that a person arrested for, charged with, or convicted of a second or subsequent offense involving the operation of a motor vehicle while intoxicated participates in the county's existing drug court program.