Legal Question in Constitutional Law in California

You can withdraw your plea until you are sentenced. After you are sentenced you can attack your plea if there is a constitutional defect in the process by moving to set aside the plea before the court that sentenced you. Otherwise an attack on your plea based on lack of representation by counsel takes the form of a writ of habeas corpus that can be obtained from the court's clerk. It must be filed in the Superior Court. Typically, problems in representation is a civil issue between you and your attorney. There must be a constitutional defect to support habeas corpus relief. Good luck.