It basically means why and how these please clearance reports are to be issued.
I think "reasons" works pretty well for "supuestos" in this context, but you could also use "circumstances," "situations," "rationale," "conditions," or possibly even "principles."

By the way, in ref. to the other suggestion above, "acuerdo" doesn't mean an "agreement" here; this is a "resolution" of the executive branch. The "procurardor" isn't agreeing with anyone when they issue these, rather they're issuing an order.