Understood. But this is proper criminal law imho.
I agree with you on principle but not in practice.
The man chose by his own free will to present himself to the world with those tattoos - he put them on his face in places nobody could miss them, to advertise these qualities he saw in himself.
To present him to a jury with his self-advertisements covered up is not an exercise in fairness; it is an exercise in deception. A fair trial does not start by deceiving a jury, and on that basis I would deem it improper.
Really? I find it hard to believe that. The marking of ones body to that extent is intimately connected to that persons beliefs and inner workings and some of those marks are direct claims of responsibility for criminal acts IIRC. To hide them, in my opinion, is to commit fraud upon the jury.