California
 

•  Illegal to use a cell phone while driving unless in hands-free mode.
• Drivers younger than 18 are prohibited from using a cell phone, even with hands-free devices.
• Enforcement is primary, meaning drivers can be stopped for this without any other traffic offense taking place.

• All drivers are prohibited from writing, sending, or reading a text-based communication while driving. Enforcement is primary.

• Children younger than 8 or shorter than 57 inches must be restrained in a child passenger restraint system in the rear seat.

• Drivers are required to slow down and vacate the lane closest to a stationary emergency response vehicle flashing emergency lights, if safe to do so, including tow trucks and Caltrans (California Department of Transportation) vehicles.  

• Riding in the cargo area of a pickup truck is prohibited.

• Seat belts are required for drivers and all passengers (ages 16 and older). Enforcement is primary.

Colorado
 

• Drivers younger than 18 are prohibited from using a wireless telephone while driving, even with hands-free devices.

• All drivers are prohibited from texting while driving. Enforcement is primary.

• Drivers must reduce speed and, if safe to do so, vacate the lane closest to stationary emergency vehicle and tow vehicles.

• All children younger than 8 are required to be properly restrained in a car seat or booster seat. 

• Riding in a pickup truck bed is prohibited unless a person is seated in an enclosed cargo area.

• Seat belts are required for the driver and front-seat passengers 16 and older. Children ages 8 to 16 must wear seat belts, no matter their position in the vehicle. 

Nevada
 

• Cell phone use while driving is prohibited unless it is being used in hands-free mode. Enforcement is primary.

• All drivers are prohibited from texting while driving. Enforcement is primary.

• Children younger than 6 and who weigh less than 60 lbs. must be secured in a child passenger restraint system in the rear seat.   

• Drivers must reduce speed and, if safe to do so, vacate the lane closest to stationary emergency vehicle and tow vehicles.

• Riding in the cargo area of a pickup truck is prohibited for children younger than 18.

• Seat belts are required for the driver and all passengers.

New Mexico
 

• Drivers are prohibited from using hand-held cellular phones in Santa Fe and Las Cruces.
• Teen drivers in instructional and provisional phases are prohibited from using any wireless devices while driving.

Text Messaging

• Teen drivers in instruction and provisional phases are prohibited from using any wireless devices while driving. 

• Children ages 5 and 6 or less than 60 lbs. must be restrained in a booster seat or appropriate safety seat. Children ages 1 through 4 or weighing less than 40 lbs. must be properly secured in a child passenger restraint device. Children younger than 1 must be placed in a rear-facing child safety seat in the rear seat, if available.

• All children younger than 18 must be properly restrained in a child restraint device or a seat belt. 

• Drivers are required to reduce speed and vacate the lane closest to emergency vehicles, if safe to do so. Does not include tow trucks.

• Riding in the cargo area of a pickup truck is prohibited for those younger than 18.

• Seat belts are required for drivers and all passengers. Enforcement is primary.

Sonora, Mexico
 

• Speed limits are posted in kilometers rather than miles per hour. 

• In Mexico, you are assumed guilty until proven innocent. This means that if you are arrested for any reason, you may be jailed until you can prove your innocence. 

• U.S. auto insurance is not valid in Mexico. A Mexico auto policy is the only form of insurance the authorities will accept as evidence of financial responsibility.
• Drivers who cannot provide this proof may be subject to arrest. Mexican auto insurance can be purchased online at http://www.az.aaa.com/insurance/mexico.

Arizona
 

• Arizona does not have a law that prohibits cell phone use for drivers.

• Drivers in Phoenix and Tucson are prohibited from texting while driving.

• Children younger than 16 are required to be properly restrained in all seats.
• Effective Aug., 2, 2012, children who are ages 5 to 8 and 57 inches or shorter must use a booster seat.
• Child restraints are required for children younger than 5.
• Enforcement is primary.

• Drivers are required to reduce speed and, if safe, vacate the lane closest to any stationary vehicles with flashing or warning lights, including stranded drivers, emergency vehicles and tow trucks.

• Arizona does not have a law that prohibits riding in the cargo area of a pick-up truck.

• Seat belts are required for driver and front seat passengers.  Children younger than 16 are required to be in seat belts in all seats.