The opinion of the court was delivered by: GRONER
Plaintiff, American Trucking Associations, Inc., is an organization of motor carriers subject to regulation under the Act, and its principal place of business is in the District of Columbia. The other plaintiffs are common carriers by motor vehicle in interstate commerce, likewise subject to regulation.
The Motor Carrier Act, which is Part II of the Interstate Commerce Act,
contains a declaration of policy, as follows:
"Sec. 202 [§ 302]. (a). It is hereby declared to be the policy of Congress to regulate transportation by motor carriers in such manner as to recognize and preserve the inherent advantages of, and foster sound economic conditions in, such transportation and among such carriers in the public interest; promote adequate, economical, and efficient service by motor carriers, and reasonable charges therefor, without unjust discriminations, undue preferences or advantages, and unfair or destructive competitive practices; improve the relations between, and coordinate transportation by and regulation of, motor carriers and other carriers; develop and preserve a highway transportation system properly adapted to the needs of the commerce of the United States and of the national defense; and cooperate with the several States and the duly authorized officials thereof and with any organization of motor carriers in the administration and enforcement of this part [chapter]."
The duties and powers of the Commission are described in Sec. 204(a):
"(1) To regulate common carriers by motor vehicle as provided in this part [chapter], and to that end the Commission may establish reasonable requirements with respect to continuous and adequate service, transportation of baggage and express, uniform systems of accounts, records, and reports, preservation of records, qualifications and maximum hours of service of employees, and safety of operation and equipment.
"(2) To regulate contract carriers by motor vehicle as provided in this part [chapter], and to that end the Commission may establish reasonable requirements with respect to uniform systems of accounts, records, and reports, preservation of records, qualifications and maximum hours of service of employees, and safety of operation and equipment.
"(3) To establish for private carriers of property by motor vehicle, if need therefor is found, reasonable requirements to promote safety of operation, and to that end prescribe qualifications and maximum hours of service of employees, and standards of equipment. In the event such requirements are established, the term 'motor carrier' shall be construed to include private carriers of property by motor vehicle in the administration of section 204  (d) and (e), 205 , 220 , 221 , 222  (a), (b), (d), (f), and (g), and 224  of this part [chapter]."
Shortly after the passage of the Act, the Commission established qualifications and maximum hours for drivers of motor vehicles operated by common and contract carriers.
It left undecided the extent of its jurisdiction over other employees. Subsequently, and after the passage in 1938 of the Fair Labor Standards Act,
the Commission again instituted proceedings to determine the previously undetermined extent of its jurisdiction. It concluded that its power over employees was limited to the promotion of safe operation, in consequence of which it had jurisdiction to establish hours of work and qualifications of drivers, but of no other employees.
Plaintiffs filed their petition June 9, 1939, asking the Commission to hear evidence and establish regulations as to all employees. The Commission declined to do so, adhered to its former ruling, and declared that any further consideration would be futile, since it had no power to do the things asked. This action was then begun against the United States and the Commission. The Administrator of the Wage and Hour Division was allowed to intervene.
At the hearing counsel stated that, if the Act be construed as plaintiffs insist, the Commission will have to prescribe qualifications and hours for stenographers, clerks, accountants, mechanics, solicitors, and other employees of whose duties and qualifications it has no special knowledge; in this function its determination would not be based upon considerations of transportation -- on which it is held to be expert -- but upon social and economic considerations, matters on which it is not qualified or equipped, and which would entail the performance of a duty wholly foreign to its normal activities. But even if this be granted, we think there is no doubt that Congress had the power to impose the challenged duty. And the answer to the query cannot be found in the fact of inconvenience to ...