awd

I rented a car at LAX at the weekend intending to use my own liability insurance. However I did not take a copy of my own policy with me.

The counter agent insisted that it would be illegal for me to drive the car unless I bought the their liability insurance since I would have no proof of insurance if I was stopped by police.

Is this correct or was I scammed ?

I know that the rental car companies do not provide any liability insurance in California but even after I bought their insurance I still had no explicit proof of insurance only an unclear entry on the rental agreement.

I noticed that their was 'a certificate of self insurance' in the glove box.

In the past I have rented without carrying my own insurance policy - was that not allowed?