You are debating a point with a colleague. Your colleague is wrong but to prove they are wrong you have to use information you know but cannot share. So, you leave things unsaid. Of course, someone who does not know the facts would also leave things unsaid by definition.

The listener knows that silence either conveys the fact that something is known but cannot be said or that nothing is known. Their inference takes the fact that you might know something but cannot say it into account. They should give you the benefit of the doubt. The benefit depends on how likely you are to know things that cannot be said. Hence, if the person leaving things unsaid is senior to the listener, the listener might defer to the speaker. Hence, seniority leads to authority via the inference content from leaving things unsaid.