Um, Bragg is attempting to enforce New York State law, not Federal law.
The current proceeding is a Grand Jury, which is a prosecutorial proceeding to demonstrate there is sufficient evidence or cause to indict someone.
If Tangerine Mussolini is indicted, he will be afforded the opportunity to defend himself in court, which is his Constitutional right.
Precedent was enstablished in the case, The State of New York vs Ham Sandwich.