Duplicate question - duplicate answer:
You almost certainly are facing two punishments for one act. The first is before the judge. He can give you a fine or possibly other penalties.
The second is the demand letter. That is an attempt by the store to legally steal from you. Stop worrying right now and go listen to your lawyer (the public defender).
Confidential information should not be disclosed in this Internet forum. This answer is not legal advice, which requires a personal connection and far more facts. This attorney does not give legal advice over the Internet. This is a general statement about law, not advice.
You are talking about two different things: the demand letter and the criminal process. Paying the demand letter has no effect on the criminal process. If you are arrested a criminal case will be filed against you whether you paid the demand or not. There is no advantage to paying it and at least one major disadvantage: the National Retailers' Theft data base (which is not a court record) keeps track of all shoplifting offenses at the larger stores. One way to get on the list is to have a criminal conviction; the other way is to voluntarily pay a civil demand letter. Don't do it.
As for any criminal charge CA does not have a true expungement process. An expungement wipes your record clean or seals it. CA instead has a dismissal statute that allows you to apply for dismissal after you have completed probation. In misdemeanor cases you must include proof of rehabilitation. After such a dismissal you will not have to report your conviction to private employers but you will have to disclose it when seeking a state job or state license (other than a driver's license).
You are best off to follow your PD's advice.
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