There are clear steps in place to take if a subpoena is ignored so I cannot see any reason but some kind of collusion for a DA's office not to follow them if a bank refuses to provide documents. In this case a large amount of money was stolen by an employee using an ATM card to withdraw funds. The employee was terminated for other reasons before the theft was known and the ATM card was never returned. The DA refused to go forward without either the card (showing the employee's name) or a copy of the card or similar from the bank saying the employee's name was on that card with that number. (Backstory:The bank is refusing because that was an unauthorized account created by a bank employee). The bank MUST have these records, inaction by the DA must indicate an improper bank/DA relationship.
It is not clear who issued the subpoena. If the DA issued the subpoena, whether or not they follow up is called "prosecutorial discretion" (not collusion), and they're under no obligation to tell any member of the public if/when or why. If you or someone you know issued and served the subpoena, it is not the DA's obligation to do anything, but yours. Civil subpoenas are issued in connection with pending lawsuits seeking some affirmative relief, and it is the person who is seeking the information who must take steps in court to have it enforced.
I think you may be suffering from some sort of delusion if you believe that the DA is colluding with a bank. S/he would have no reason to and certainly not over your case. Failing to abide by a subpoena is contempt. This is a crime. I very highly doubt a bank disregarded a subpoena. How do you know that the DA even issued one? The DA has discretion in deciding which cases s/he does or does not wish to pursue. You don't like their decision it's pretty much too bad (though you can consider going to the AG or if certain types of crimes were committed involving certain banking institutions you can got to the Feds).
There are many reasons the DA may decide not to prosecute a case. If the DA is intent on prosecution he can bring the case to a Grand Jury and believe me the bank will respond to the subpoenas. The DA may have evaluated the case and found other weaknesses. I do not understand your standing in this thing. It seems the money was not taken from any person's account. If the bank does not want to pursue it and the DA either why are you upset?
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