What is going to happen to someone who is over 18 and was in a car accident and was driving without a license in California?

Depends on who was At Fault: If you were at fault, then you would get a citation (TICKET) for driving without a license (See 12500(a)C.V.C.- an infraction) and would also be cited for the violation that occurred leading to the car accident (i.e., illegal turn, fail to stop at stop sign/signal, etc....) If you weren't at fault, the other person would be cited. Just because you don't have a license doesn't automatically mean you're at fault. If you're an out-of-state driver with a valid license, then you'd be treated as if you had a valid California license.