I don’t know for sure — but I think one must be a licensed lawyer — in any case, OBO and Mooch both ‘VOLUNTARYILY” returned their licenses to practice lawyer.
One possible reason is to beat the command for them to be disbarred.
Lawyer is not constitutionally required but would be a hard sell to appoint one who wasn’t. But with Zero? All things are possible in Ratlandia!
You don't actually have to be a lawyer to sit on the Supreme Court.
At least there's no constitutional requirement.
They didn't return their licenses - they voluntarily suspended them with the option of reactivating.
Barack Obama went on to retired status, but that wouldn't make him ineligible for a judgeship.