Where can I find the laws regarding car insurance? Igot a ticket while driving my boyfriends car.

While I do not practice in CA, I practice in NY and in this state the reason for getting a letter from the Insureance company, rather than just displaying an Insurance Card is because they've had too many incidents of them being forged. So they usually insist upon a letter from the insurance company saying the car was insured on the day in which you received the ticket.

As for proving you "had permission" to use the car, that should be obtained from the owner of the vehicle rather than the insurance company. You should be able to bring in your boyfriend to have him state that you had his permission to use his car - if it was his car. If not, then bring in the owner or get a letter from the owner giving you permission for that date and time to use the car. That should do the trick.

Good luck.