Of course, since this is now available to local & federal cops & prosecutors, same as any other law enforcement database, any exculpatory information will naturally be discoverable by defense attorneys.
I'm suddenly reminded of two stories. One was my Civics teacher who grew up in a dry country. Every four years they got a new sheriff. Because hey after you've earned a quarter of million in bribes (circa 1965) why not retire. And another who mentioned when she was a teenager the feds busting two local sheriffs deputies for trafficking cocaine.
You really want a corrupt sheriff or drug dealing cops to have access to all the stuff the NSA does?
Sounds a lot like the argument the government makes about encryption. "Do you really want terrorists and pedophiles to be able to hide from law enforcement? What about a ticking timebomb scenario?"
Right?
Right?