Prosecutors make verbal arguments before the court, arguments that supposedly are rational. This is part of their attempt to convince their own people --- that being their fellow men and women, and that being their fellow rational beings --- that so-and-so is guilty, of some offense. Foucault has talked about this, which is the subject of law, or the "juridical" or something like that, as I recall. In the book called "Truth and Power" he begins a survey of this stuff from early on in European history, with Germanic tribes who had just arrived to occupy former areas of the Roman Empire. and, in this period, the early medieval, is an account he gives of the quirky of German tribal laws. There isn't always all that much reason involved. For example, for one of these tribes, when twelve persons from your own clan say that you are not culpable you are thereby cleared. You become "innocent" ---- now you are free, and not "guilty" (yeah, I know: "accused") anymore.
What is always necessary and indispensable in any case is the conceit of rationality, the appearance. Think about it: what persons are always concerned about would be the appearances. That's what they are always found to be doing. They are always concerned about their appearance. This is universal. Everyone wants to look good.
The first persons in society who are going to disrespect rationality (while wearing nice clean outfits, you know what I mean?) are the prosecutors (next up are law enforcement officers, for they too always "explain" things to the offender, like why he is a shitty human being, or why he needs to be put to jail).
Well, two black guys have now been freed on DNA evidence (not human reason) after something like maybe 18 or 20 years of imprisonment. Their alleged crime (now traced, by DNA, not human reason, to another guy, him being already in prison for rape or something) --- which strangely enough they "confessed"? to --- showing yet another side of quirky human nature --- was something like rape or murder (I think murder but Ah'm gettin' confused. Dear me).
In this particular case, the prosecutors actually backed off, and requested their presiding judge to "vacate." Whatever that means. Good for you, fellows. "Pretty Vacant." (I wonder what the Sex Pistols have to do with this?)
We try to make rational sense but words are pretty inexact. That is why writing is such an art; and, also, a craft. A craftsman (there is a somewhat relevant Richard Sennett book out there) has all kinds of little decisions to make, in the course of creating a similar object to others.
So many times we see men and women try to "nail" something down, in rational argument. But Foucault's excursions show us something like a long plank of wood that has a series of crooked nails jammed in.