In this subchapter, "weight enforcement officer" means:
(1) a license and weight inspector of the Department of Public Safety;
(2) a highway patrol officer;
(3) a sheriff or sheriff's deputy;
(4) a municipal police officer in a municipality with a population of:
(A) 100,000 or more; or
(B) 74,000 or more in a county with a population of more than 1.5 million;
(5) a police officer certified under Section 644.101; or
(6) a constable or deputy constable designated under Section 621.4015.