If the poor thing was conscious and able to turn in the car, get in the back seat and brace herself into the air pocket, why couldn't she have rolled down a window.
Ted Kennedy should still be charged with negligent manslaughter. At the least.
Probably scared witless and panicked.
It is easy to get disoriented if you are trapped in a car underwater, especially if you have been drinking enough to leave a party with Ted. If you are in an air pocket you are not going to want to turn around and swim down away from the pocket.