Further, § 56-5-4730 clearly evinces legislative intent that even a discretionary brake light must be in good working condition by prefacing the good-working-condition requirement with the conditional phrase "when a vehicle is equipped with a stop lamp. . . ." The word "when" in context here means "in the event that" or "whenever." (5) "When a vehicle is equipped with a stop lamp" therefore means "whenever" or "in the event that" a vehicle is equipped with a stop lamp. This phrase has meaning only if it refers to discretionary stop lamps since reference to the mandatory single stop lamp would not require this conditional phrase. See In re: Decker, 322 S.C. 215, 471 S.E.2d 462 (1995) (a statute should be construed so that no word, clause, provision, or part is rendered superfluous).
The Court of Appeals's interpretation of § 56-5-4730 requiring that only a single stop lamp be in good working condition overlooks the "when a vehicle is equipped" phrase which refers back to the first sentence of the statute providing for both mandatory and discretionary stop lamps. We hold, under a plain reading of § 56-5-4730, it is unlawful to drive with a non-functioning brake light. Accordingly, the traffic stop in this case was valid. The Court of Appeals's decision is
REVERSED.