It is not uncommon for the DA to direct an investigation. Whether or not what the sheriff's investigator did was improper or not, at this point the case was dismissed. Be happy!
The DA's office is who presents to the Grand Jury whatever information gets presented, and they can request more information from the Sheriff if they want to. Since the charge was dismissed, this falls into the No Harm, No Foul category. In other words, even if anything was improper, which is not clear to me, no one is going to spend time and resources looking into it when they have more pressing cases.
This answer is intended to be taken as general information and not as specific legal advice. You should always consult a qualified attorney and make him familiar with all the relevant facts in order to get proper legal advice. Every case is different, and they must be evaluated on a case-by-case basis. David N. Smith 812 W. 11th Street, Suite 201 Austin TX 78701 (512) 457-0100 defenseattorneysmith.com
Not sure exactly what happened here from the summary you give. But, I will try to answer. First, the DA actually does have a role in a sheriff's investigation. That role is to advise on legal issues, and to suggest directions he or she would like the investigation to go. For example, I am presently special prosecutor for a felony investigation. Part of my job is to tell the investigator what I want investigated. Because grand jury proceedings are secret by law in Texas, I am concerned that you say the testimony to the grand jury was false. Unless you were present in the room, how would you be privy to that? Or, is there a civil suit pending? If so, you need to talk about the questions you are raising with your lawyer in that case.
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