delivered the opinion of the court.

The petitioner, an unmarried woman and a native of Russia, came to the United States in the year 1897 or 1898, at the age of about twelve years, accompanied by *83 a man who had promised to marry her, and during the four years immediately following she practiced prostitution in the City of New York and supported her companion with the proceeds of her prostitution; she then left that city, and thereafter continuously practiced prostitution in various parts of the United States, including different towns and cities in the States of Washington, Arizona, and Texas. In the month of March, 1908, she returned to Russia for the purpose of visiting her mother, intending at the same time to return to this country; she reentered the United States at the port of New York in June, 1908, accompanied by her mother, at which time petitiоner falsely represented, for the purpose of facilitating her landing, that she was Mrs. Joseph Fiore, and the wife of an American citizen; at the time of this, her second entry, she intended to continue the practice of prostitution in the United States, and almost immediately upon being admitted she engaged in that practice, and was continually engaged in it until September 21, 1909, on which date she was arrested in a house of prostitution in Phoenix, Arizona, upon a warrant of arrest duly issued by the Acting Secretary of Commerce and Labor under the provisions of the Immigration Act of February 20, 1907, c. 1134, 34 Stat. 898. Upon a hearing properly accorded to her, the foregoing facts were established, and an order of deportation was made upon the ground that she was a prostitute and wаs such at the time of her entry into the United States; that she entered the United States for the purpose of prostitution; and that she had been found an inmate of a house of prostitution and practicing the same within three years after her entry. She obtained a writ of habeas corpus, which, after a hearing, was dismissed by the District Court for the Southern District of New York. Upon appeal, the Circuit Court of Appeals аffirmed the order of dismissal (sub nom. Ex parte Hoffman, 179 Fed. Rep. 839). The present writ of cer *84 tiorari was then allowed because of the division of judicial opinion upon the question presented, which is whether the provisions of the Immigration Act of 1907 respecting admission and deportation apply to an alien such as the petitioner, who, having remained in this country for more than three years (in this instance for more than ten years), after first entry, and having gone abroad for a temporary purpose and with the intention of returning, again seeks and gains admittance into the United States.

The pertinent provisions of the act of 1907 are set forth in the margin. 1 So far as the present question is concerned, the act is not materially different from — certainly not less stringent than — the act of March 3, 1903 (32 Stat. 1213, c. 1012). The Circuit Court of Appeals in the present case followed its own decision in Taylor v. United States, 152 Fed. Rep. 1, which was based upon the act of *85 1903, and in which it was held that while the provisions of the act of March 3,1891 (26 Stat. 1084, c. 551) had benn construed as restricted to “alien immigrants,” the act of 1903 had been so framed as to cover aliens whether immigrants or not. In behalf of the petitioner it is contended that the court erred in its judgment as to the purpose of Congress in modifying the language of previous acts on adopting the revision of 1903, arid that this act and the act of 1907, as well as those that preceded them, when properly construed, refer to “alien immigrants” exclusively.

The acts of 1903 and 1907 being revisions or compilations (with some modifications), of previous acts pertaining to the same general subject-matter, a reference list, in chronological .order, is for convenience set forth in the mаrgin. 1

*86 In a number of cases in the Federal District and Circuit Courts, it was held that the provisions of the act of March 3, 1891, and the acts that preceded it, relating to the exclusion and deportation of persons arriving in the United States from foreign countries, were confined in their operation to “alien immigrants”; and that this term did not include aliens previously resident in this country, who had temporarily departed with the intention of returning. In re Panzara (1892), 51 Fed. Rep. 275; In re Martorelli (1894), 63 Fed. Rep. 437; In re Maiola (1895), 67 Fed. Rep. 114; In re Ota (1899), 96 Fed. Rep. 487. The same view was expressed by ‍​​‌​‌‌​​​‌​‌​​‌​‌​​​​‌‌​‌​‌​‌​‌​​‌​‌‌​‌​‌​​‌​​​‌‍the Circuit Court of Appeals for the Ninth Circuit in Moffitt v. United States (1904), 128 Fed. Rep. 375.

Upon the reasoning and authority of these cases, a similar construction was given to the act of 1903 in United States v. Aultman Co. (1906), 143 Fed. Rep: 922 (affirmed by the Circuit Court of Appeals, 148 Fed. Rep. 1022), the attention of the court apparently not having been directed to the question whether any significant change had bеen made in the law by the revision of 1903.

But in Taylor v. United States (1907), 152 Fed. Rep. 1, which was a review by the Circuit Court of Appeals for the Second Circuit of a judgment of conviction upon an indictment for a misdemeanor for permitting an alien sailor to land in New York, contrary to § 18 of the act of *87 1903, which made it the duty of the owners, officers, and agents of any vessel bringing an alien to the United States to adopt due precautions to prevent the landing of any such alien, etc., the court reviewed the changes made by Congress in the. revision of 1903,. “following decisions of the courts which tended to relax the provisions of earlier acts,” and, finding that § 18 of the act of 1903 substantially reenacted a part of § 8 of the act of 1891, employing the term “alien” in the place of the term “alien immigrant,” and that similar changes were made in other parts of the act, came to the conclusion that the change evinced an intent of Congress to use the word “alien” in its ordinary and unqualified meaning. This decision was reviewed in this court, and the judgment was reversed, but upon the ground (207 U. S. 120, 124) that § 18 did not a,pply to the ordinary case of a sailor deserting while on shore leave.

Shortly after the decision of the Circuit Court of Appeаls in the Taylor Case, the Circuit Court of Appeals for the Third Circuit, in Rodgers v. United States, ex rel. Buchsbaum (1907), 152 Fed. Rep. 346, held that the provision of § 2 of the act of 1903, enumerating the classes of aliens to be excluded from admission into the United States, and amongst them “persons afflicted with a loathsome or with a dangerous contagious disease,” and the provision, of § 19, for the deportation of “aliens brought into this country in violation of law,” could not be construed so as to extend to aliens domiciled in this country; affirming In re Buchsbaum, 141 Fed. Rep. 221. In United States v. Nakashima (1908), 160 Fed. Rep.-842, the Circuit Court .of Appeals for the Ninth Circuit adopted the same view of the act of 1903 expressed in the Aultman and Buchsbaum cases, rejecting that adopted by the Court of Appeals in Taylor v. United States.

On the other hand, the latter decision has been followed in a number of cases arising under the act of 1907, which in this, respect does not materially differ from the act of *88 1903. Ex parte Petterson (1908), 166 Fed. Rep. 536; United States v. Hook (1908), 166 Fed. Rep. 1007; United States v. Villet (1909), 173 Fed. Rep. 500; Ex parte Hoffman (1910), 179 Fed. Rep. 839 (being ‍​​‌​‌‌​​​‌​‌​​‌​‌​​​​‌‌​‌​‌​‌​‌​​‌​‌‌​‌​‌​​‌​​​‌‍the case now under review); Sibray v. United States (1911), 185 Fed. Rep. 401; United State's v. Williams (1911), 186 Fed. Rep. 354; United States v. Sprung (1910), 187 Fed. Rep. 903; Frick v. Lewis (1912), 195 Fed. Rep. 693; Siniscalchi v. Thomas (1912), 195 Fed. Rep. 701. Contra, Redfern v. Halpert (1911), 186 Fed. Rep. 150; and see United States v. Rodgers (1911), 191 Fed. Rep. 970.

The authority of Congress over the genеral subject-matter is plenary; it may exclude aliens altogether, or prescribe the terms and conditions upon which they may come' into or remain in this country. Chinese Exclusion Case, 130 U. S. 581, 603; Nishimura Ekiu v. United States, 142 U. S. 651, 659; Fong Yue Ting v. United States, 149 U. S. 698, 713: Lem Moon Sing v. United States, 158 U. S. 538, 547.

The question, therefore, is not the power of Congress, but its intent and purpose as expressed in legislation. The cases that have held the immigration acts not to apply to domiciled aliens returning after a temporary absence have been rested in part upoh the use of the term “immigration” in the titles of the respective acts, and in part upon the employment of that or similar terms in the enacting clause's.

As authority for a liberal interpretation of the acts, two decisions of this court have at times been referred to, which have, however, little, if any, present pertinency. Holy Trinity Church v. United States, 143 U. S. 457, held that the Contract-labor Law of February 26, 1885 (23 Stat. 332, c. 164), did not forbid a contract for employing á. clergyman. The-act was construed according to its spirit rather, than its letter, and in view of its title, the evil intended to be remedied, the circumstances surround *89 ing the appeal to Congress for legislation, and the reports of committees in each House, it was held to be the legislative purpose simply to stay the influx of cheap unskilled labor. Since this decision, an express exception has been made of “ministers of any religious denomination.” In Lau Ow Bew v. United States, 144 U. S. 47, this court held that the provision of the Chinese Restriction Act of May 6, 1882 (22 Stat. 58, c. 126, § 6) as amended by act of July 5, 1884 (23 Stat. 115, c. 220), requiring every Chinese merchant coming into this country to procure and produce a certificate from the Chinese Government, did not apply to Chinese merchants already domiciled in the United States, who, having left this country for some temporary purpose, sought to reenter it upon their return to their homes here. But this decision was based in part upon the language of the particular statute and in part upon the fact that our treaty with China gave to Chinese merchants domiciled in the United States the right of egress and ingress, and the other rights, privilеges, and immunities enjoyed in this country by the citizens or subjects of the most favored nation.

The legislative history of the act of 1903 demonstrates that the elimination of the word “immigrant” and other equivalent qualifying phrases was done deliberately. The bill originated in the House of Representatives, where the Committee Report declared that its general purpose was “to bring together in one aсt scattered legislation heretofore enacted in regard to the immigration of aliens into the United States ... to amend such portions thereof as have been found, either as the result of experience in administering the law or of judicial decision, to be inadequate to accomplish the purpose plainly intended thereby; and to add thereto such further provisions as seemed to be demanded by the consensus of enlightened public opinion.” H. Rept. 982, 57th Cong., 1st Sess. The report of the Senate Committee likewise explained *90 the bill as being in the main a reenactment of existing laws on the subject of immigration, stating — “The necessity for such reenactment is due in part to the fact that, as a result of judicial decisions, as well as 'of administrative experience, the efficiency of such laws to accomplish the evident рurpose of their enactment has been shown to be materially less than appeared to be the case at the time of such enactment, and therefore a new expression of the legislative will ‍​​‌​‌‌​​​‌​‌​​‌​‌​​​​‌‌​‌​‌​‌​‌​​‌​‌‌​‌​‌​​‌​​​‌‍upon the subject of immigration has become desirable.” The Senate inserted the word “immigrant” in one place, but it was eliminated in conference. S: Rept. 2119, 57th Cong., 1st Sess.; S. Doc. 62, 57th Cong., 2d Sess. Cong. Record, Yol. 36, p. 2949, 57th Cong., 2d Sess.

Counsel for petitioner cites the debates in Congress as indicating that the act was not understood to refer to any others than immigrants. But the unreliability of such debates as a source from which to discover the meaning of the language employed in an act of Congress has been frequently pointed out (United States v. Trans-Missouri Freight Ass’n, 166 U. S. 290, 318, and cases cited), and we are not disposed to gо beyond the reports of the committees. Holy Trinity Church v. United States, 143 U. S. 457, 463; Binns v. United States, 194 U. S. 486, 495; Johnson v. Southern Pacific Co., 196 U. S. 1, 19.

It is- earnestly insisted that the * omission of the word “immigrant” is of little consequence, because it does not apply at all to the excluding section. It is said that the words “alien immigrant” did not occur in the acts of 1875,1882,1885, or 1887, and did not occur in the excluding section of the act of 1891, but only in its eighth section —that .which related to manifesting. But in the act of 1893, “To facilitate the enforcement,” etc., each section was made to apply to “alien immigrants.” The force of the argument pretty well disappears when we recall that it was in spite of the absence of the word “immigrant” in the *91 excluding clause that courts had held that because the word occurred in the title and in other provisions of the pertinent acts, the excluding clauses likewise werе confined to immigrants, in the sense of aliens who had no domicile in this country. Of course, there were other considerations; the extreme hardship in individual cases where the aliens had long been resident in this country, and the practically uncontrolled authority of the executive officers of the Government, being among them. But, whatever considerations may have combined to bring about the judicial interpretation of the acts that preceded the Revision of 1903, the committee reports already cited sufficiently show that the language of the new act was chosen not for the purpose of adopting, but in order to avoid, that interpretation.

Upon a review of the whole matter, we are satisfied that Congress, in the act of 1903, sufficiently expressed, and in the act оf 1907 reiterated, the purpose of applying its prohibition against the admission of aliens, and its mandate for their deportation, to all aliens whose history, condition or characteristics brought them within the descriptive clauses, irrespective of any qualification arising out of a previous residence or domicile in this country.

The excluding section as found in the act of 1907 contains in its own language the clearest answer to the entire argument for the petitioner. It reads as follows (34 Stat. 898, c. 1134, § 2): “That the following classes of aliens shall be excluded from admission into the United States: All idiots, imbeciles, feeble-minded persons, epileptics, insane persons, and persons who have been insane within five years previous; persons who have had two or more attacks of insanity at any time previously; paupers; persons likely to become a public charge; professional beggars; persons afflicted with tuberculosis or with a loathsome or dangerous contagious disease; persons not comprehended within any of the foregoing excluded classes who are found to be *92 and are certified by the examining surgeon as being mentally or physically dеfective, such mental or physical defect being of a nature which may affect the ability of such alien to earn a living; persons who have been convicted of or admit having committed a felony or other crime or misdemeanor involving moral turpitude; polygamists, or persons who admit their belief in the practice of polygamy, anarchists, or persons who believe in or advocate the overthrow by force or violence of the Government of the United States, or of all government, or of all forms of law, or . the assassination of public officials; prostitutes,- or 'women or girls coming into the United States for the purpose of prostitution or'for any other immoral purpose; persons who procure or attempt to bring in prostitutes or women or girls for thе purpose of prostitution or for. any other immoral pujóse; persons hereinafter called contract laborers, who have been induced or solicited to migrate to this country by offers or promises of- employment or in consequence of agreements, oral, written or printed, express or implied, to perform labor in this country of any kind, skilled or unskilled;” etc., etc. None оf these excluded classes (with the possible exception of contract laborers, whose exclusion depends upon somewhat different considerations) would be any less undesirable if previously domiciled in the United States. And besides, the section contains its-own specific .provisos and limitations, and these, on familiar principles, strongly tend to negative any other and implied exception. •

There remains, therefore, only the use of the word “immigration” in the title of the act to furnish support for petitioner’s contention. But it is only in a doubtful case that the title of an act can .control the meaning of the enacting clauses, and there is no such doubt here. United States v. Fisher, 2 Cranch, 358, 386; Holy Trinity-Church v. United States, 143 U. S. 457, 462; Coosaw Mining Co. v. South Carolina, 144 U. S. 550, 563; Patterson v. *93 Bark Eudora, 190 U. S. 169, 173; Cornell v. Coyne, 192 U. S. 418, 430.

It was not intended, in the opinion of this- court in Taylor v. United States, 207 U. S. 120, 126, to intimate an opinion with respect to the construction of § 18 of the act of 1903 that is inconsistent with the result now rеached. There the Circuit Court of Appeals (one judge dissenting) had construed that section as excluding even the ordinary sailor, if an alien; basing this construction upon the changes wrought by Congress in the revision of 1903. This court, speaking by Mr. Justice Holmes, said: “A reason for the construction adopted below was found in the omission of the word ‘immigrant’ which had followed ‘alien’ in the earlier acts. No doubt that may have been intended to widen the reach of the statute, but we see no reason to suppose that the omission meant to do more than to avoid the suggestion that no one w^,s within the act who did not come here with intent to remain. It is not necessary to regard the change as a mere abbreviation, although the title of the statute is ‘An act to regulate the immigration of aliens into thе United States.’ ” Of course, this language was employed with reference to the facts of that case, and was not intended to negative a purpose on the part of Congress to bring within the reach of the statute aliens who had previously resided in this country. In that case there was no element of previous residence.

Judgment affirmed.