Harlan F. Stone,
Nashville St. Railway v. Wallace…
“ The states are left free to regulate their own judicial procedure. Hence changes merely in the form or method of procedure by which federal rights are brought to final adjudication in the state courts are not enough to preclude review of the adjudication by this Court, so long as the case retains the essentials of an adversary proceeding, involving a real, not a hypothetical, controversy, which is finally determined by the judgment below. ”
