GR
I believe from a legal perspective the Prosecution would object to an FC on the grounds of lack of impartiality. As a controller the FC has a vested interest in the outcome of the case. Furthermore, as a specialist in the field, the FC would have massive influence during jury deliberations (the others would naturally ask the resident expert for their view). Such an expert is undesirable for the prosecution, when they are certainly going to see this case for the absolute travesty which it so clearly is.
RB