Louis Brandeis, Piedmont Railway Company v. United States…
“ If, as is contended, the Commission was without jurisdiction, the railway is as free to proceed with the construction as if the application had not been made and the Commission had not acted. Nothing done by the Commission can prejudice the railway's claim to immunity in any other proceeding.It is true that, if the railway builds without having secured a certificate, it may suffer serious loss. For a court may hold, in an appropriate proceeding, that the railway is within the purview of paragraph 18. ”
