Traffic Laws
The basic speed law and posted limits
New Mexico's basic speed law is the backbone of every speed question: never drive faster than is safe for existing conditions, even below the posted limit. Rural interstates are posted up to 75 mph and urban interstates 65 mph; most other roads default to 55 mph and residential or business districts to 30 mph unless a sign says otherwise. In a designated safety corridor, fines for moving violations are doubled.
Right-of-way
At a four-way stop, the first vehicle to stop goes first. If two arrive at the same moment, the driver on the left yields to the driver on the right. A left-turning driver yields to oncoming traffic going straight or turning right. Vehicles entering a public road from a driveway, lot, or private road yield to traffic already on the road. Pull right and stop for emergency vehicles using lights and siren.
New Mexico rules
- School bus: flashing red lights mean stop in both directions on an undivided road. On a divided highway with a physical median, opposite-side traffic does not stop.
- Move Over law: approaching stopped emergency, tow, or maintenance vehicles with flashing lights, change lanes if possible or slow down.
- Seat belts are primary enforcement for all occupants; children under 7 need an appropriate child restraint.
- Handheld phone use and texting are illegal for all drivers.
Worked example
You and another car stop at a four-way stop at the same moment; you plan a left turn and the other car goes straight. Reasoning: simultaneous arrival gives priority to the car on the right, and the left-turn rule also applies because a left-turner yields to any vehicle going straight. You wait for the other car, then turn.
Traps that cost marks
Treating a green light as an automatic right-of-way; forgetting a right turn on red needs a full stop first; stopping for a school bus across a divided highway when no stop is required; ignoring doubled fines in a safety corridor.