If it's their vehicle and the vehicle wasn't stolen, the owner should know who was driving it. Courts do compel people to testify sometimes (when it is not self-incriminating).
They are not required to know who is driving their registered vehicle at all times, just that anyone that is allowed to drive it has a license.
They are not required to know who is driving their registered vehicle at all times, just that anyone that is allowed to drive it has a license.