Final answer:
Passenger restrictions in GDL laws are implemented to limit liability and create a safer driving environment for novice drivers.
Step-by-step explanation:
The main purpose for passenger restrictions as part of Graduated Driver Licensing (GDL) laws is to limit liability. By placing restrictions on passengers, such as limiting the number of passengers or prohibiting young drivers from driving with other young passengers, GDL laws aim to reduce distractions and create a safer driving environment for novice drivers. These restrictions help prevent accidents and minimize the risk of injuries to both the drivers and passengers.