It sounds to me as if your son went through the RCC/EDC court process (either your soon went to superior court in Mesa or 2nd/3rd floor of south court tower in downtown Phoenix. Often times the first plea offers aren't worth taking so the case needs to get out of the RCC/EDC level and into the trial level. That is why your son was then indicted because that is a step in that process. Your son will now be assigned to a new lawyer who will start trying to get a better offer or at least try to get the original offer back.
Attorney David Kephart is an experienced Trial Attorney and Jury Consultant. He is the recipient of the Arizona Attorneys for Criminal Justice President's Award and the recipient of the International Academy of Trial Lawyers Commendation for Excellence in Trial Advocacy. His response to your question is intended to be a general statement of law, should not be relied upon as legal advice, does not create an attorney/client relationship, and does not create a right to continuing email exchanges.
The answer to your initial question is that a defendant has very limited time to accept the plea agreement. The State does not have to extend a plea agreement. However, when they do extend a plea agreement, they must act in good faith. Therefore, they can not give you a plea and tell you that you have twenty minutes to accept this.
The issue, however, does not seem to be with the timeframe for the plea agreement. Instead, it seems that the issue centers on your son's communication with and representation by the public defender. He needs to relay all of this information to his new public defender and/or a retained attorney for further analysis.
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