Though transparency and oversight are important democratic norms, and a tripartite system of checks and balances was put in place to foster them, there are cases where they have failed. The Edward Snowden and Daniel Ellsberg affairs serve as exemplars.
The arc of the majoritarian approach to regulation and emergency responses also usually works. It can be argued that a 51% majority will err on the side of correctness and that a 79% majority is probably even more correct. A 99% majority would lead us to be circumspect, as it would be indicative of an authoritarian mandate.
There are cases where leaders are given emergency powers—in the case of state disasters and wartime powers in the event of national emergencies. These arise in cases where the process of deliberation would likely lead to untimely, non-optimal consequences.
It is for this reason that roundtables or justice leagues are better for deliberations among superheroes, and perhaps this is their moral equivalent of an emergency response mechanic.
Just as elected officials are representative agents for change, subject to oversight and answering to the public, superheroes should be subject to the same constraints.
Without revealing their identities, the equivalent of a referendum—that could be called in short order—and the introduction of mechanics for direct democracy—such as electronic voting on mobile devices, would enable rapid and rational responses.