Depends on whether the info was priviledged or discoverable. Violation of the attorney-client priviledge is grounds for a claim of ineffective assistance of counsel. If the violation is such that a court cannot protect your right to a fair trial by forbidding the state from using the information, you would have a good argument for dismissal for violation of your right to effective assistance of counsel. Examples of information that *might* warrant dismissal: location of buried body that gives police more evidence against defendant, names of aliases that lead cops to a criminal history they use against you that they wouldn't have found otherwise, notes from a meeting where you told your attorney you did it. BUT, if the court discovery order instructs the attorney to turn over 'all information regarding X in his possession', you're SOL.
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This is not legal advice and you are not my client. Double check everything with your own attorney and your state's laws.