A potentially testable or disprovable fact or widely published statistic is the only acceptable evidence in most political and media communications. Arguments advanced without evidence of this kind (documented facts, clippings from credible media sourcees, government's own published statistics, i.e. Statistics Canada ), tend to have little credibility if they remain unevidenced.

Normally if evidence is advanced the exact source and the authority that backs it, to which one is expected to defer, is required. See evidence/source/authority for more about this aspect of the TIPAESA structure.