Texas Basic Peace Officer Certification Practice Exam

Which of the following is a key indicator of potential drug use during a traffic stop?

1. Excessive laughter

2. Odor of alcohol

3. Pupil dilation or constriction

4. Unfamiliarity with the vehicle

The correct answer is: Pupil dilation or constriction

Pupil dilation or constriction is a key indicator of potential drug use during a traffic stop because various substances can significantly affect the size of the pupils. For instance, stimulants like cocaine or methamphetamine may cause pupils to dilate, while opioids or depressants can cause them to constrict. Observing these physiological changes can provide law enforcement with vital clues regarding the presence of drug use, aiding in their assessment and subsequent actions during the stop. In contrast, while excessive laughter, the odor of alcohol, and unfamiliarity with the vehicle might suggest unusual behavior or intoxication, they are not as direct indicators of drug use specifically. Excessive laughter may be due to a variety of social factors or anxiety rather than drug influence. The odor of alcohol pertains more directly to alcohol consumption, while unfamiliarity with a vehicle could suggest a lack of ownership or knowledge that is not necessarily linked to drug use. Thus, among the options, pupil changes provide the most specific and reliable indication of potential drug use.