What is a common clue of impairment during a traffic stop?

Slurred speech is a notable indicator of impairment during a traffic stop, particularly when assessing a driver's condition. This symptom often suggests that an individual may be under the influence of alcohol or drugs, as these substances can affect the central nervous system and alter a person's ability to articulate words clearly. Law enforcement officers are trained to look for specific signs of impairment, and slurred speech is frequently one of the first and most recognizable signs that prompts further investigation.

While other signs such as inability to provide identification, unusual attire, or overly aggressive behavior may raise certain concerns, they are not as directly indicative of impairment as slurred speech. Inability to provide identification could stem from various factors, not necessarily intoxication. Unusual attire may not have any connection to a person's cognitive or motor functions. Overly aggressive behavior can occur for various reasons, including stress or personal issues, which do not necessarily relate to impairment from substances. Thus, slurred speech stands out as a clear and common clue of impairment for law enforcement officers during traffic stops.