Tubbius couldn't speak to add more on this sort of decision, as the stated language was agreed upon and voted upon.
You would have to narrow it down to ask about a specific section of the reasoning, as it is not a ban for any single specific reason.
Given that this is a security matter though, there will always hypothetically be protection of sources, and information not put into publicly viewable record. That would kept private to the Council of Lazarene Security, and the Court (if they need to see it for legal reasons). The mandate not requiring a full display of evidence by the CLS in public, was applied to this and past CLS votes.
To require a full revealing of evidence would break with past procedure, so a vote would need to be held to decide whether that would be changed, or what would be permitted to be revealed. Past CLS votes haven't commonly revealed evidence.