The legality of traffic stops for Fourth Amendment purposes are analyzed under the standard articulated by the United States Supreme Court in Terry v. Ohio, 392 U.S. 1, 88 S.Ct. 1868 (1968). Under Terry, the court must determine the reasonableness of the search or seizure by asking (1) whether the officer’s action was justified at its inception; and (2) whether the officer’s action was reasonably related in scope to the circumstances which justified the interference in the first place. Terry, 392 U.S. at 19, 88 S.Ct. at 1878. In assessing whether the intrusion was reasonable, an objective standard is utilized: would the facts available to the officer at the moment of the seizure or search warrant a man of reasonable caution in the belief that the action taken was appropriate. Terry, 392 U.S. at 21-22, 88 S.Ct. at 1880. Also see Davis v. State, 947 S.W.2d 240 (Tex.Crim.App. 1997).
As I have mentioned before, Texas courts routinely recognize that a law enforcement officer may lawfully stop a vehicle and conduct a brief investigation when he observes a traffic violation. Strauss v. Texas, 121 S.W.3d 486, 490 (Tex.App. – Amarillo 2003, pet. ref’d.). The decision to stop a vehicle is reasonable when the officer has probable cause to believe that a traffic violation has occurred. Walter v. State, 28 S.W.3d 538, 542 (Tex.Crim.App. 2000).
The legality of a traffic stop is determined by the factors relied upon by a law enforcement officer in making the decision to initiate the stop. What the officer saw and his interpretations of his observations are critical. To successfully challenge a traffic stop, a thorough investigation is required and, quite often, a motion to suppress evidence must be filed. Over the next two months, I am going to discuss four specific traffic laws that are commonly used by law enforcement officers in the Amarillo area to initiate traffic stops and explain how these stops are challenged in court.