Traffic Law and Enforcement
What the exam tests
This domain tests New Hampshire Motor Vehicle Code enforcement: stop authority, speed and lane violations, reckless driving under RSA 265:79, and impaired driving under RSA 265-A. Expect questions on reasonable suspicion, probable cause, implied consent, and field sobriety testing.
Core rules
- A traffic stop requires reasonable suspicion of a violation, not probable cause.
- RSA 265-A:2 prohibits driving while under the influence; RSA 265-A:3 covers aggravated DWI. The per se limit for adults is 0.08; lower limits apply to underage and commercial drivers.
- Field sobriety tests must be administered and documented properly; observations of driving, odor, speech, and coordination build probable cause.
- An officer may order a driver out of the vehicle after a lawful stop.
- Reckless driving requires a manner showing disregard for safety, not merely a minor violation.
Worked example
An officer sees a car cross the fog line twice, then brake abruptly. The officer stops the car. The driver has slurred speech and an odor of alcohol. The officer conducts standardized field sobriety tests, observes clues, and arrests for DWI. Reasoning: the lane violations supplied reasonable suspicion for the stop; the driving plus personal observations supplied probable cause for arrest. The officer should document each clue, not just the conclusion.
Traps
- Saying probable cause is needed to make a traffic stop.
- Treating a refusal to perform field tests as automatic guilt.
- Charging reckless driving for a simple speeding violation.
- Failing to document the driving observations that justified the stop.