I won't go on here about what the "right" answer is to these questions. In brief, it seems right to me, as folks at the user forum concluded, that probation records probably need to be disclosed, at least in a proceeding to revoke or adjudicate after a deferred adjudication disposition. As for jail calls, I find the AG's opinion fairly confusing, and confused, with respect to both the MMA and Brady doctrine. The bottom line seems to be, according to the opinion, that disclosure is required only if investigators or prosecutors actually listen to the calls, and that all calls might be deemed in the "control" of the prosecutor if their contract with the recording company gives them "unfettered" access. Good luck to prosecutors making sense of that, and to defense attorneys who might be stuck with a lot of jail calls to review when cautious prosecutors just disclose the whole kit and kaboodle. (My advice to DA's offices is to revisit your contracts to limit your access to the calls!)
The more interesting point for me is this. The queries are a good reminder that even under a statutory scheme that specifies, in essence, full disclosure by the state of anything that is "material to any matter involved in the action" (39.14(a)), questions will arise about the substantive scope of the obligation. Open file is not a "set it and forget it" regime. (I've been learning about this in some detail as the Reporter to the ABA's task force on criminal discovery standards, where task force members from North Carolina have shared accounts of that state's continuing process of revisiting and respecifying its "open file" discovery law.) In fact, the more sweeping the legal disclosure obligation, the more that questions arise about items on the margins. That's because from the prosecutor's standpoint, the burden of sorting through masses of documentation for the "material" bits becomes laughably burdensome; and on the flip side, the burden to the defense of receiving huge quantities of documentation that might contain a scintilla of relevant information is equally if not more deleterious.
A corollary observation is that neither the MMA nor any other discovery regime can fully remove discretion - prosecutorial discretion in particular - from the equation. Prosecutors are necessarily making judgment calls about where to draw the line. That's probably inevitable: no statute can fully specify its parameters. But one of the potential dangers of open file regimes is a kind of lulling of defense counsel into reliance on the discovery packet. The probation and jail calls conversations are good reminders to defense counsel that affirmative queries will still be required both to acquire relevant and helpful information in the control of the state, and to tee up for judicial determination some of the judgment calls that prosecutors might be making.