Can motor accident case be registered as unnatural death cases

If it is a death due to road traffic accident then it cannot be changed to natural death.

If the driver is not having valid driving license then he will face criminal law also besides the compensation case.

A fatal motor accident case is termed as "unnatural" death, wherein the negligent driver shall be booked under Section 304 A IPC

A road accident death is an unnatural death. Generally the police will chargesheet the driver for rash and negligent driving. Ultimately it is for the court to decide whether it was fault of the driver, fault of the deceased or any other reason.