Legal Question in Credit and Debt Law in California

You can do that only if you are admitted to practice law by the Supreme Court of the State of California and are an active member of the California Bar. You cannot represent anyone, not even your wife. That would be practicing law without a license which is a crime. You can obviously help her fill out the papers based on information she provides without charging her but she has to go personally and she has to sign all the necessary papers.

Filling out your own papers (aside from the obvious problem of your not being a lawyer and it being a crime to attempt to represent your wife) is a fool's errand. If winning the case is important to you, use a lawyer. If you have a good defense to a credit card suit and you win, the credit card company in most cases has to pay your attorney fees.

You have already committed a crime by filling out and filing her answer for her. She must do it herself or hire a California licensed attorney in good standing.