What happens if I violate my ACD by being arrested again for shoplifting?

The good news is that legally you are not in a worse place then you were prior to accepting the ACD. Upon violating an ACD, the DA should move to restore that case to the calendar, which the judge will grant if you were re-arrested. Your status will be exactly the same as it was prior to accepting an ACD, presumed innocent, with the burden on the DA to prove your guilt.

The bad news is that the DA and judge gave you a very big break. You had the chance to dismiss and seal all of the criminal charges against you and you blew it. Not only did you squander the chance, the judge and DA will believe that you are continuing to commit the same type of crimes. Expect that they will not be looking to show leniency this time. That does not mean they will be seeking jail as punishment but you will have a much tougher time this go around.  With the right attorney, it may still be possible to resolve both these cases without having a permanent criminal record that cannot be expunged.

Legal disclaimer: All answers are for information purposes only. Answering this question or any future questions does not form any attorney-client relationship. Be mindful, that answers are limited by the limited facts presented by the questioner and are not meant to take the place of competent legal advice by an attorney fully informed of all the facts surrounding your case. However, be aware that nothing posted in a public forum such as this can be deemed confidential or privileged communication. For a privileged private consultation, contact me at 212-385-8600 or via my website www.reasonabledoubtny.com