When evidence/source/authority is attached to an issue/position/argument tree and a deadline "time horizon" is set for a decision to be made, the entire structure is called TIPAESA for time/issue/position/argument/evidence/source/authority. Some political parties and online forums have structured meeting agendas in this form so that issues can be substantially debated before the meeting, with input from anyone, even anonymous trolls.
Those who question the utility of such deep trees should keep in mind how much time is typically consumed arguing about the validity of evidence in politics. And how much effort can be saved if one is willing to cite their experts to prove a point, whether one accepts the authority of those experts personally or not. To restrict accepting authority to extremely limited contexts such as validating specific sources of certain types of evidence, is one way to ensure that conflicts over which authority to accept, does not become overly fractious.
An extremely simple example is the position:Republicans are unbiblical on abortion which has many arguments in its favour. One of these arguments is that Moses permitted abortions to occur. What is the evidence for this? The Book of Exodus. What is the source of that? Generations of Torah scholars copying the Old Testament so perfectly that they would formally hold a funeral for a manuscript that had even a single malformed letter in it. What is the authority claimed? To believers, that of God "himself". To non-believers, the generally good historical reliability of Old Testament timing, especially as compared to the official chronicles of Egypt and Babylon which were much more self-aggrandizing and less honest about leaders' behavior.
So while there is dispute over the authority and the degree to which it might have divinely inspired the source, there is no dispute that this is evidence, and it is certainly admissible in all arguments made for and about those who believe in the Bible as a source of moral values and moral examples. Period.
A more complex example is the way debates are conducted in modern courtrooms under British and American rules of evidence. Certain sources are simply not allowed, e.g. hearsay is excluded, and circumstantial evidence has only a certain limited status. Authority to include or exclude evidence is made by a judge, and, even if the decision is later re-examined "on appeal", new evidence is restricted from being entered so as not to challenge the authority of the prior court and evidence rulings directly, or the sources that conveyed this evidence (defense and prosecution) which are delicately balanced during a criminal trial.
These extremely specific rules about evidence, sources, and authority, have evolved because of extreme abuses of these to advance courtroom arguments in favour of positions that turned out, later, to be provably false or unfair to the defendant or community. No adversarial process exists without clear rules of evidence/source/authority to regulate what can be introduced.