"This is a suit brought by the appellants against Robert Vance Davidson, Attorney General of the state of Texas, John W. Stephens, Comptroller of the state of Texas, and John W. Robbins, Treasurer of the state of Texas, for the purpose of enjoining them from taking any action in the matter of estimating, assessing, or attempting to enforce the collection of a certain tax, purported to be levied upon the appellants and other railways of the state of Texas by an act of the Twenty-Ninth Legislature of the state of Texas, entitled `An act imposing a tax upon railroad corporations, the receivers thereof, and other persons, firms and associations of persons owning, operating, managing or controlling any line of railroad in this state for the transportation of passengers, freight and baggage, or either, equal to one per cent. of their gross receipts, and providing for the collection and payment thereof, and repealing the existing tax on gross passenger earnings of railroads,' which act was approved April 17, 1905, and took effect 90 days after the adjournment of the Legislature; that is, upon the 17th day of July, 1905. Laws 1905, p. 336, c. 141. For convenience, said act will hereinafter be referred to as the `Gross Receipts Tax Bill,' a copy of which is attached to appellants' petition herein. The grounds on which the injunction was sought are set up in full in appellants' petition, and are in substance as follows:
"The lines of railway owned and operated by appellants are situated wholly within the state of Texas, and appellants are, by the laws of the state of Texas and of the United States, authorized to connect with other lines of railway in said state, or lines outside of the state at the state line, thereby constituting through lines for the transportation of goods, wares, and merchandise, express matter, mails, and passengers between points in the state of Texas, and between points in said state and points in other states and territories of the United States and foreign countries. That appellants are now, and had been for many years prior to the passage of said gross receipts tax bill, common carriers of freight and passengers, and required by the Constitution and laws of the state of Texas and the Constitution and laws of the United States to receive and transport freight and passengers between said points within the state of Texas, and between points in said state and between other points in the United States and foreign countries, and that as to such latter transportation they are, and have been since their existence as corporations, interstate and international carriers of such transportation. That for the year ending June 30, 1905, they received for the transportation of interstate and international commerce a large portion of their gross receipts; an accurate statement of their gross receipts from such sources, and from interstate business, as well as from the carriage of mail and express matter and other sources, being set forth in detail in appellants' said petition. That by the terms of said gross receipts tax bill the said John W. Stephens was required to estimate, assess, and enforce the collection from appellants of 1 per cent. upon their entire gross receipts derived from all sources, and appellants allege in their petition that such tax is unconstitutional and void, because same is in violation of the third subdivision of section 8, art. 1, of the Constitution of the United States, which provides that Congress shall have power to regulate commerce with foreign nations, and among the several states, and with the Indian tribes, and is in violation of the Constitution and laws of the United States.
"That the Constitution of the state of Texas provides that property shall be taxed only in proportion to its value, and that all taxation must be equal and uniform, and that all property of railroad companies must be assessed by the tax assessors of the several counties in which said property is situated, including so much of the roadbed and fixtures as is in each county, except that the rolling stock may be assessed in the county where the principal office of the company is located, and requires the Comptroller to apportion the assessment of such rolling stock among the several counties through which the road runs in proportion to the distance it runs in each county. That said Constitution of the state also provides that all property, whether owned by persons or corporations, must be assessed for taxes and the taxes paid in the county where situated, excepting that the taxes of nonresidents may, by a two-thirds vote of the Legislature, be authorized to be paid at the office of the Comptroller, and also provides for the election in each county of a tax assessor to assess the property of persons and corporations for taxation, and constitutes the commissioners' courts of the respective counties of the state a board of equalization, with power and authority to equalize, as near as may be, the valuation of all property subject to or rendered for taxation. That in pursuance of said constitutional provisions the Legislature of the state has heretofore passed laws in accordance therewith, and property in the state, whether owned by natural persons or corporations, has been subjected to such local assessments for taxation by the assessors
and has been equalized by the board of equalization, constituted as aforesaid. That the assessors in making such assessments, and the boards of equalization of the respective counties in approving and equalizing the same, are required by law to give a just, fair, and proper valuation of all property subject to taxation, and their action in making the assessment is not subject to revision by any tribunal or department of government, but the same is made final and conclusive when approved by the board of equalization, and is a judicial determination of the value of the property assessed, which is final and conclusive and not subject to review by any authority in the state of Texas. That appellants, in accordance with the Constitution and laws of the state, rendered to the assessors of taxes in the respective counties through which their said lines of railway run and in which they are situated, and the assessors of taxes in each of said counties assessed, and the boards of equalization approved and equalized, all of appellants' property situated in each of said counties, respectively, including their rolling stock, which was assessed, and the assessment approved as aforesaid, for the year 1905; and the action and judgment of said several assessors in assessing the same, and the action and judgment of the several boards of equalization in approving and equalizing such assessments has become final, and now fixes and establishes the value of all of appellants' property for taxation situated and being in the state of Texas, and there is no method provided by or known to the law for the revision of such assessments and valuations. That all taxes to which appellants are subject for state and county purposes are included in such assessments, and appellants will be compelled to pay, and will pay, the taxes assessed against them for the year 1905 as aforesaid. That there are various independent school districts organized in said state, and various organized cities, towns, and villages through which appellants' said lines of railway run, which have in like manner, by authority of the Constitution and laws of the state, assessed and levied against appellants' property situated in such school districts, cities, towns, and villages, respectively, for the year 1905, the taxes authorized to be levied by them, and these appellants will be compelled to pay the taxes so levied and assessed. That the latter assessments are and will be equalized and fixed by the authorities of such cities, towns, villages, and school districts in the manner provided by law, and have and will thereby become fixed, established, and conclusive, without any power of revision in...