delivered the opinion of the Court.
This is a petition by Williams, the tax commissioner of Nebraska, and 71 county treasurers asking for a writ of mandamus to be directed to District Judge Woodrough of the federal court for that State. A rule to show cause issued,
Nebraska has provided for the assessment of railroád property by. a State Board of Equalization. Compiled Statutes, 1922, §§ 5839, 5840. ' After the board completes its valuation, it is required to return to the county clerk of every county in which the railroad has property, a statement showing the proportion of the railroad that lies within the county, its average valuation per mile, and the valuations that shall be placed to the credit of each of the governmental subdivisions of the county. The board is authorized to fix the rate of taxation for state purposes; and it transmits to the county clerk a statement of the rate so established. The county treasurers are ex officio collectors of all taxes levied within their respective counties whether for state or for local purposes. §§ 5847-5850, 5904, 5905, 5996.
The Railroad seeks in its suit to enjoin the collection of the taxes for 1923 on the ground that the equality clause of the Fourteenth Amendment was violated in making the assessment. It alleged that its property was assessed by the state board at 122% of its actual value, while the property of other taxpayers was assessed locally at not
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more than 60% of its value; that this discrimination was systematic and intentional; that the valuation of its property fixed by the state board had been certified to the clerks of the various counties and entered on the tax lists; that the taxps were about to become delinquent; and that the Company was without adequate remedy at law. It prayed that the court fix the percentage of the tax levied which it should/pay to the county treasurers in tentative settlement, for a temporary restraining order, and for interlocutory and final injunctions. Pursuant to an order of the district judge, the motion for an interlocutory injunction came on for hearing, in November, 1923, before a court of three judges constituted as provided in § 266 of the Judicial Code. Because certain of the legal questions presented were deemed similar to those involved in
Chicago, Burlington & Quincy R. R. Co.
v.
Osborne,
The Osborne case was decided on April 28, 1924. On June 23, 1925, the district court, again composed of three judges, appointed, on motion of the Railroad, a special master to take evidence. His report was filed on January 31, 1928. Soon thereafter, the defendants made the motion that the District Judge call two additional judges to his assistance on final hearing. He was not required to do this unless the suit was one in which, as provided in § 266, it is sought to restrain “ the enforcement, operation, or, execution of any statute of a State by restraining the action of any officer of such State in the enforcement or execution of such statute, or in the enforcement or execution of an order made by an administrative board or commission acting under and pursuant to the statutes of such State . . . upon the ground of the unconstitutionality of such statute.” We are of opinion that Judge Woodrough properly denied the motion.
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A case does not fall within § 266 unless a statute or an order of- an administrative board or commission is challenged as contrary to the Federal Constitution.
Oklahoma Gas Co.
v.
Russell,
For the purpose of jurisdiction in federal courts, the difference between the function of regulating, expressed
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in orders of a railroad or like commission, and the function of fact-finding is vital. Determinations of an administrative board which are merely findings of fact are not reviewable,
Keller
v.
Potomac Electric Co.,
Obviously an ássessment which is not “ a statute of or an authority exercised under any State ” within the meaning of § 237,.before amended by the Act of 1925, cannot be a statute or an order of an administrative board or commission under § 266. The orders contemplated by § 266 are directed to railroads or others, of whom action, or non-áction, is commanded, as it is by a statute. *273 Compare Sultan Ry. & Timber Co. v. Department of Labor and Industries, supra. Since an assessment by a state board of equalization has none of the qualities that would be associated with “ orders,” it cannot have been the sort of state administrative function which Congress had in mind when/by the amendment of 1913, it declared the scope of § 266 so as to include suits in which the injunction was sought on the ground of the unconstitutionality of an administrative order. 1
Under the Act of February 13, 1925, the final hearing is not required to be before three judges unless the application for an interlocutory injunction was required to be. In a large majority of the cases of this character in which applications for an interlocutory injunction have been made, they have been heard before a single judge; and the propriety of the practice has not been questioned by this Court. 2 As we hold that the action of the state and *274 county boards which is alleged to be discriminatory, is not an order within the meaning of § 266, we have no occasion to consider whether the lower court was right in holding that the “ county treasurers are not officers of the State of Nebraska,” or whether there are other reasons' why the suit is not within the scope of that section.
Rule discharged.
Notes
The purpose of the amendment, as stated by Mr. Clayton, who had charge of the bill in the House, was “ to put the order of a State railroad commission upon an equality with a statute of a State; in other words, to give the' same force and effect to the order of a State .railroad commission as is accorded under existing law to a State statute.” 49 Cong. Rec. 4773.
This appears to have been the uniform practice where the assessment was made by local officials.
Union Pacific R. R. Co.
v.
Board of Commissioners of Weld County,
