delivered the opinion of the court.
This is a suit in mandamus. The trial court sustained a demurrer to the petition, and a judgment of dismissal was entered. The petitioners bring the cause here for review, assigning as error the sustaining of the demurrer.
The petition for a writ of mandamus, with the exhibit attached thereto, discloses the following facts:
The Sixty-fifth Congress of the United States, at its second session, in December, 1917, by a joint resolution duly adopted, proposed an amendment to the Constitution of the United States, popularly known as the “National Prohibition Amendment.”
On January 15, 1919, the General Asesmbly of the State of Colorado ratified the proposed amendment by a concurrent resolution, which, after reciting the Joint Resolution of Congress, proposing the amendment, contains the follow*265ing language: “Therefore, Be It Resolved, by the General Assembly of the State of Colorado, That the said proposed amendment to the Constitution of the United States of America be and the same is hereby ratified by the General Assembly of the State of Colorado.” Thereafter, and prior to June 10, 1919, referendum petitions were prepared and signed, and were tendered, for filing, to the Secretary of State. In these petitions, the signers “order and demand” that the resolution of. the General Assembly, ratifying the National Prohibition Amendment, “shall be submitted to the legal, voters for their adoption or rejection at the polls,” etc. The three persons designated to represent the signers of the referendum petition are the .petitioners in this mandamus suit, the plaintiffs in error.
The Secretary of State of Colorado, who is the respondent in this case, the defendant in error, refused to file the petitions, or to so act in the premises, whereby the concurrent resolution in question would be submitted to the voters at the next general election for their adoption or rejection. It is to compel him to thus act, and to file the petitions, that, the writ is sought.
The demurrer which was sustained, and the argument thereon, present two questions, namely:
1. Does Article V of the federal Constitution, providing for ratification of proposed amendments “by the legislatures of three-fourths of the several states,” forbid the exercise of the referendum upon a joint or concurrent resolution of the General Assembly ratifying a proposed amendment to the Constitution of the United States?
2. Does Section 1 of Article V of the Constitution of the State of Colorado authorize and permit the exercise of the referendum upon such resolution?
Our discussion will be confined, chiefly, to the provisions of the state Constitution relating to the referendum; in other words, to the second question above mentioned.
Section 1 of article V of the state Constitution, so far as the same is pertinent to this cáse, reads as follows (italics ours):
*266“Section 1. The legislative power of the state shall be vested in the general assembly' consisting of a senate and house of representatives, both to be elected by the people, but the people reserve to themselves the power to propose laws and amendments to the constitution and to enact or reject the same at the polls independent of the general assembly, and also reserve power at their option to approve or reject any act, item, section or part of any act of the general assembly. The first power hereby reserved by the people is the initiative, and at least eight per cent, of the legal voters shall be required to propose any measure by petition * * *. The second power hereby reserved is the referendum, and it may be ordered * * * against any <aet, section or part of any act of the general assembly * * *. Referendum petitions shall be addressed to and filed, with the secretary of state not more than ninety days after the final adjournment of the session of the general assembly, that passed the bill on which the referendum is demanded. The filing of a referendum petition against any item, section or part of any act, shall not delay the remainder of the act from' becoming operative. The veto power of the governor shall not-extend to measures initiated by, or referred to the people. All elections on measures referred to the people of the state shall be held at the biennial regular general election, and all such measures shall become the Imo or a part of the Constitution, when approved by a majority of the votes cast thereon * * *. This section shall not be construed to deprive the general assembly of the right to enact any measure * * *. The secretary of state shall submit all measures initiated by or referred to the people for adoption or rejection at the polls, in compliance herewith.” From the above quoted constitutional amendment, it is seen that the people, in granting legislative powers to the general assembly, reserved to themselves “the power at their option to approve or reject any act * * * of the general assembly.”
The controversy in the instant case, upon the question now under consideration centers about the word “act” in *267the clause last above quoted. It is the contention of the plaintiffs in error that the word is broad enough to comprehend not only a general statute, enacted by a bill, but also such a concurrent resolution as the one involved in this case.
The presumption is in favor of the natural and popular meaning in which the words are usually understood by the people who have adopted them. 12 C. J. 705. In the popular sense, the term “act” refers to a general statute, or law, enacted by a bill. A resolution, concurrent or otherwise, is commonly referred to as a “resolution.” The rule that the words and terms of a Constitution are to be interpreted and understood in their most natural and obvious meaning, also tends to exclude a resolution from the meaning of the term “act.” An act is a law, and under our state Constitution, “no law shall be passed except by bill.” Sec 17, Art. V. It is only in the sense of a law, a statute, that the term “act” is used in the initiative and referendum, constitutional amendment. This conclusion is aided by the fact that the term in question is used in connection with the word “bill,” where it is provided, that referendum petitions shall be filed, etc., after the adjournment of the general assembly that “passed the bill on which the referendum is demanded.” The concurrent resolution involved in the instant case was not passed by a bill; neither does it have the enacting clause, required for “the laws of the state” by Section 18, article V, of the state Constitution. A resolution is not a bill. May v. Rice, 91 Ind. 551. The distinctions between a bill and a resolution are well defined. Henderson v. Lithographing Co., 2 Colo. App. 257, 30 Pac. 40. Under these circumstances, we may adopt the following language, contained in Lithographing Co. v. Henderson, 18 Colo. 262, 32 Pac. 417. “The concurrent resolution adopted by the senate * * * and by the house * * *, cannot be held to be a law of the state. The resolution was not passed by ‘Bill’ as provided by sections 17 and 18 of the Constitution.”
In Herbring v. Brown, 92 Ore. 176, 180 Pac. 328, the supreme court of Oregon, without a dissenting vote, held that the various sections of their initiative and referendum *268constitutional amendment “apply only to proposed laws, and not to legislative resolutions, memorials, and the like,” and therefore did not apply to the legislative resolution involved in that case, which was a joint resolution of their Legislative Assembly, ratifying the National Prohibition Amendment. The' Oregon Court in arriving at its conclusion, considered and adopted the sense in which the terms “bill” and “act” were used in the Constitution before the initiative and referendum amendments were adopted. The same method may properly be employed in the instant case, with the same result, holding that the term “act,” as usted in the various parts of the Constitution, “means a bill which has been enacted by the Legislature into a law,” and further that: “The initiative and referendum amendments were passed and should be construed in the light of the construction put upon the terms ‘bill’ and ‘act’ by the instrument they proposed to amend, and taking this view it must be held that, as a joint resolution is neither a bill nor an act, it is not subject to the referendum.” The decision of the Oregon court, holding that a legislative resolution ratifying an amendment to the federal Constitution could not be referred to the people, was not based on any grounds going beyond the provisions of the state Constitution itself, or the matters hereinbefore discussed. What has already been said in this opinion is sufficient to dispose of this case, resulting in the determination that our state Constitution does not authorize or permit the exercise of the referendum on any concurrent resolution, or upon the one involved in the instant case.
There are other reasons why the resolution involved in this case is not subject to the referendum. One of these is suggested by the argument of the plaintiffs in error, wherein they state that “it is not reasonable to believe” that the people intended, when adopting the initiative and referendum amendment, “to deny to themselves the right to adopt or reject a measure which, once adopted, can never be amended or repealed except by the concurrence of three-fourths of the States of the Union.” In ordinary legislative *269matters, the general assembly, of course, derives its power from the people of the state, and the people may reserve to themselves any power they desire, but in the matter of the ratification of a proposed amendment to the federal Constitution, the general assembly does not act in pursuance of any power delegated or given to it by the state Constitution, but exercises a power which it possesses by virtue of the fifth article of the Constitution of the United States. That article provides that proposed amendments “shall be valid, * * * as parts of this constitution, when ratified by the legislatures of three-fourths of the several states.” A ratification by a general assembly, of a proposed amendment- to the federal Constitution, is not, therefore, lawmaking legislation for the state, subject to approval or rejection by the referendum.. Further, in this connection, we adopt the language of In Re Opinion of Justices (Maine), 107 Atl. 673, 674, as follows: “* * * The state Legislature in ratifying the amendment, as Congress in proposing it, is not, strictly speaking, acting in the discharge of legislative duties and functions as a law-making body, but is acting in behalf of and as representative of the people as a ratifying body, under the power expressly conferred upon it by article 5.' The people, through their Constitution, might have clothed the Senate alone, or the House alone, or the Governor’s Council, or the Governor, with the power of ratification, or, might have reserved that power to themselves to be exercised by popular vote. But they did not. They retained no power of ratification in themselves, but conferred it completely upon the two houses of the Legislature; that is, the Legislative Assembly.” The conclusion just stated, as it is expressed in the paragraph above quoted, results from our opinion upon the question, raised by the demurrer, whether c-r not the federal Constitution, in Article V thereof, permits a referendum) of a resolution of a general assembly which ratifies a proposed amendment, to the- Constitution of the United States. Article V provides for a ratification of proposed amendments by the “legislatures.” It is the contention of the plaintiffs in error *270that the word “legislature” thus used means “the whole legislative power of the state.” This definition is intended to be made applicable in the instant case by including- the legislative power of the people as given by the referendum. In our opinion, however, the term “legislature” as used in Article V of the federal Constitution, means that body of persons composing the ordinary representative lawmaking; body of the state. Under that definition it necessarily follows that the people have no power to ratify a proposed amendment to the federal Constitution, by a popular vote, and therefore cannot exercise the referendum upon such a ratifying resolution as is involved in the instant case. The conclusion we reach in this matter is the one adopted, and ably supported, in the opinion of the Justices of the Supreme Judicial Court of Maine, all justices concurring, reported in 107 Atl. 673. A discussion of this subject, which arrives at the same result, may be found in the dissenting opinion of Justice Parker in State v. Howell (Wash), 181 Pac. 928. The judgment is affirmed.
Affirmed.
En Banc.
Mr. Justice Burke and Mr. Justice Teller concur in the conclusion. Mr. Justice Denison dissents.