Reasonable suspicion is less than probable cause, but more than no evidence at all - a hunch. It is information which is sufficient to cause a reasonable law enforcement officer, taking into account his or her training and experience, to reasonably believe that the person to be detained is, was, or is about to be, involved in criminal activity (LU, 2008).
A traffic stop is a seizure within the meaning of the fourth amendment. In the Whren v. United States (1996) case, the unanimous court held that as long as officers have a reasonable cause to believe that a traffic violation occurred, they may stop any vehicle (Oyez, 2011). Due to the fact a taillight on the vehicle appeared to be broken, Officer Smith had reasonable suspicion to make the initial stop. A broken taillight is a traffic violation.
The constitutional origin for police protective searches comes from the U.S. Supreme Court case of Terry v. Ohio (1968). The court held that a police officer may temporarily detain a person for questioning if the officer has a reasonable suspicion that criminal activity may be involved. The officer may pat down the person for weapons only if the officer has the additional reasonable suspicion that the pat down is necessary for safety reasons (Roberson, Wallace & Stuckey, 2012). This type of pat down is now called the "Terry stop" in many jurisdictions. The pat down that Officer Smith performed on the driver was very legal because, the car fit the general description of the suspected car in a recent road side killing of a fellow police officer. Smith was assuring her safety.
Exigent circumstances are situations that demands unusual or immediate action and this allows people to circumvent usual procedures - emergency conditions. These are situations in which a police officer can take immediate action to effectively make an arrest, search, or seizure for which probable cause exists. This can be done without first obtaining a warrant (USL, 2014). The exigent...