Am I liable for my deceased mother's credit card debt? I also had an extra authorized card, but the account was hers.

It is very possible that ffor those debts that you personally charged they could come to you, but in general children are not liable for their parents debts.

Also once she passed, her estate, home, furniture, car and other items would need to be sold to pay these debts, so you also need to talk to the administer of her estate.