(a) The commission by rule may establish minimum requirements for the training, testing, and certification of peace officers to conduct polygraph examinations for the purpose of:
(1) a preemployment examination of a candidate applying for a position that requires a license under this chapter; or
(2) a criminal investigation.
(b) The commission shall adopt rules prohibiting a peace officer from conducting a polygraph examination for a purpose described by Subsection (a) unless the officer:
(1) completes a training course approved by the commission; and
(2) passes an examination administered by the commission that is designed to test the officer's knowledge of investigative polygraphy.
(c) The commission shall issue a certification to conduct polygraph examinations to a peace officer who applies for the certification, completes the required training, and passes the required examination.