The insured motorist would be responsible for the damages to the car and our medical bills correct? Would we have to file a lawsuit? Even if the car we were in was uninsured?
I spent thirty five years in the insurance industry so here's a few things you should know.
1 - When somebody rear-ends a stationary vehicle that person is almost invariably 100% at fault. More details might change that percentage depending on where you were parked, when you were parked, why you were sitting in a vehicle with no driver at the time, and any other applicable circumstances.
2 - Assuming that the other driver is 100% at fault you would be entitled to compensation for your injuries which would include medical bills, lost earnings, other expenses necessitated by the accident, and pain and suffering (see number 3).
3 - In California if you are the owner or operator of the uninsured vehicle you could not collect pain and suffering per Section 3333.4 of the Civil Code. However, that would not apply if you and your wife were just passengers and did not own or operate the vehicle.
4 - You don't necessarily have to get a lawyer or file a lawsuit. In cases where the fault of the other driver is clear (citation or no citation) like in a rear-ender, the other driver's insurance company is likely going to settle rather quickly if your claim is reasonable. And, if not, you have up to two years to file I lawsuit if necessary.
5 - By "reasonable" I mean that if you suffered "whiplash" (aches and sprains) that takes modest treatment, medication, and minimal medical bills you can probably just deal with the other driver's insurance company on your own.
6 - However, if the injuries were serious, expensive, and recovery took a long time, you would be wise to consult a personal injury attorney.
7 - California is a "comparative" negligence state, not a "contributory" negligence state. The California Supreme Court abandoned the "50/50 no one takes anything" doctrine in Li v. Yellow Cab Co (1975). Even if you turned out to be 50% negligent (unlikely) you would still be entitled to 50% of your damages.