After analyzing over 10 years of vehicle crash data, the AAP has concluded, "The most dangerous thing that U.S. children do as part of daily life is ride in a car. Motor vehicle crashes remain the leading cause of death for children 4 years and older."
While car seat safety laws vary by jurisdiction, child safety seat recommendations are nationally recognized. As of August 2018, it is now recommended everywhere that rear-facing child safety seats be used for infants and toddlers from ages 2 -4 years old. As the CDC site says, "For the best possible protection, infants and toddlers should be buckled in a rear-facing car seat, in the back seat, until they reach the maximum weight and/or height limits of their car seat."
Here are the child safety seat laws for your jurisdiction:
And here are the CDC national reccomdations for car seats, booster seats and child restraint: