nstitution requires a hearing it requires a fair one, held
before a tribunal which at least meets currently prevailing standards of
impartiality.[117] An opportunity must be given not only to present
evidence, but also to know the claims of the opposing party and to meet
them. Those who are brought into contest with the Government in a
quasi-judicial proceeding aimed at control of their activities are
entitled to be fairly advised of what the Government proposes and to be
heard upon the proposal before the final command is issued.[118] But a
variance between the charges and findings will not invalidate
administrative proceedings where the record shows that at no time during
the hearing was there any misunderstanding as to the basis of the
complaint.[119] The mere admission of evidence which would be
inadmissible in judicial proceedings does not vitiate the order of an
administrative agency.[120] A provision that such a body shall not be
controlled by rules of evidence does not, however, justify orders
without a foundation in evidence having rational probative force. Mere
uncorroborated hearsay does not constitute the substantial evidence
requisite to support the findings of the agency.[121] While the Court
has recognized that in some circumstances a "fair hearing" implies a
right to oral argument,[122] it refuses to lay down a general rule that
would cover all cases.[123] It says: "Certainly the Constitution does
not require oral argument in all cases where only insubstantial or
frivolous questions of law, or indeed even substantial ones, are raised.
Equally certainly it has left wide discretion to Congress in creating
the procedures to be followed in both administrative and judicial
proceedings, as well as in their conjunction."[124]

JUDICIAL REVIEW

To the extent that constitutional rights are involved, due process of
law imports a judicial review of the action of administrative or
executive officers. This proposition is undisputed so far as questions
of law are concerned, but the extent to which the courts should and will
go in reviewing determinations of fact has been a highly controversial
issue. In St. Joseph Stock Yards Co. _v._ United States,[125] the
Supreme Court held that upon review of an order of the Secretary of
Agriculture establishing maximum rates for services rendered by a stock
yard company, due process required that the Court exercise its
independent judgment upon the facts to determine whether t